The present invention mainly relates to a yarn
monitoring device adapted to monitor a travelling yarn, and
a method of monitoring the same.
2. Description of the Related Art
10 A yarn winding machine configured to wind a yarn
around a bobbin such as a spinning machine and an automatic
winder is conventionally known. This type of yarn winding
machine includes a yarn monitoring device (yarn clearer).
An optical yarn monitoring device irradiates the travelling
15 yarn with light and measures transmitted light transmitted
through the yarn or reflected light reflected by the yarn
to monitor the state of the yarn in real time and detect
a yarn defect (portion with abnormality in the quality of
the yarn).
20 Japanese Unexamined Patent Publication No.
2013-204190 and Japanese Patent No. 3707413 disclose a yarn
winding machine equipped with this type of yarn monitoring
device.
The yarn monitoring device (clearer) of Japanese
25 Unexamined Patent Publication No. 2013-204190 includes a
clearer head with an LED and a yarn unevenness sensor. The
clearer is configured to carry out a contamination
determination process to determine presence/absence of
abnormality such as contamination of the clearer head. In
30 the clearer of Japanese Unexamined Patent Publication No.
2013-204190, a process of adjusting a drive voltage which
3
is applied to the LED is carried out prior to the
contamination determination process so that the voltage
corresponding to the detection signal when nothing is
arranged in the yarn path of the yarn monitoring device
5 becomes a voltage defined in advance. With this
configuration of Japanese Unexamined Patent Publication No.
2013-204190, the abnormality such as contamination of the
clearer head can be accurately detected.
The yarn monitoring device (yarn thickness detector)
10 of Japanese Patent No. 3707413 carries out a process of
adjusting a circuit constant of the substrate so that the
output signal becomes zero under a state when the yarn does
not exist in the detection region at a timing instructed
from the unit controller in the doffing operation.
15 Japanese Patent No. 3707413 can effectively suppress
occurrence of shift in the zero point according to such a
configuration.
The yarn monitoring device of Japanese Patent No.
5283003 relates to a yarn clearer of a capacitance type
20 instead of an optical type. Japanese Patent No. 5283003
discloses distinguishing the factor the clearer signal
changes are due to solid foreign substance particles
contained in the yarn from the factor the clearer signal
changes are due to local humidity fluctuation.
25 In the yarn winding machine, the yarn to be wound is
traveled at high speed, and thus foreign substances such
as fiber waste tend to easily produce at the periphery
thereof. Since the fiber waste is light weight, the fiber
waste floats around the yarn winding machine and may enter
30 the detection region of the yarn monitoring device.
As described above, in the yarn monitoring device
4
disclosed in Japanese Unexamined Patent Publication No.
2013-204190 and Japanese Patent No. 3707413, the process
of adjusting the drive voltage which is applied to the LED
and the process of adjusting the circuit constant of the
5 substrate to have the output signal to zero are carried out
under a state when the yarn is not arranged in the detection
region of the yarn monitoring device so that the yarn can
be accurately monitored. However, if the foreign
substances enter the detection region or separate from the
10 detection region, the accuracy in the monitoring of the yarn
usually lowers greatly. Specifically, even if the
above-described processes are carried out under a state
when the foreign substances are not present in the detection
region, when the foreign substances enter the detection
15 region thereafter, the state of the yarn cannot be
accurately evaluated. The same may also occur in the
following case. If the above-described processes are
carried out under a state where the foreign substances
enters the detection region and separates from the
20 detection region thereafter, the state of the yarn cannot
be accurately evaluated thereafter.
With regards to this, Japanese Patent No. 5283003
describes specifying the factor the clearer signal changes,
but does not disclose the influence of the foreign
25 substances entering the detection region or separating from
the detection region.
BRIEF SUMMARY OF THE INVENTION
The present invention has been made in view of the
30 above circumstances, and a main object thereof is to provide
a yarn monitoring device capable of accurately monitoring
5
the yarn even when foreign substances enter the detection
region or separate from the detection region, and a
corresponding monitoring method.
The problems to be solved by the present invention
5 are as described above, and now, the means and effects for
solving such problems will be described.
According to a first aspect of the present invention,
a yarn monitoring device having the following configuration
is provided. Specifically, a yarn monitoring device
10 includes a light projecting section, a light receiving
section, and a control section. The light projecting
section is adapted to project light on a detection region
through which a yarn can travel. The light receiving
section is adapted to receive the light projected from the
15 light projecting section. The control section receives a
detection value corresponding to a light receiving amount
of the light receiving section. The control section
includes an evaluating section, a light projection
adjusting section, and a foreign substance responding
20 processing section. The evaluating section is adapted to
evaluate a state of the yarn existing in the detection
region based on the detection value. The light projection
adjusting section is adapted to carry out a light projection
adjusting process of adjusting a drive control value of the
25 light projecting section so that the detection value
becomes a predetermined value in a state where the yarn does
not exist in the detection region. The foreign substance
responding processing section is adapted to carry out a
foreign substance responding process when the detection
30 value is outside a predetermined foreign substance
determination range continuously for a predetermined
6
foreign substance determination time in the state where the
yarn does not exist in the detection region. The light
projection adjusting section carries out the light
projection adjusting process again when the detection value
5 is outside a normal range, which is a range of a detection
value set in advance, so as to have a wider width than a
width of the foreign substance determination range in the
state where the yarn does not exist in the detection region
According to a second aspect of the present invention,
10 a yarn winding machine including the yarn monitoring
device; and a winding section adapted to wind a yarn that
passes through the yarn monitoring device to form a package
is provided.
According to a third aspect of the present invention,
15 a yarn monitoring method is provided.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view schematically illustrating a
yarn winding unit according to one embodiment of the present
20 invention;
FIG. 2 is a side view of a yarn winding unit
illustrating a state where yarn ends are caught by a first
yarn catching device and a second yarn catching device;
FIG. 3 is a side view of the yarn winding unit
25 illustrating a state where the yarn ends are guided to a
yarn joining device by the first yarn catching device and
the second yarn catching device;
FIG. 4 is a perspective view illustrating a
configuration of a clearer;
30 FIG. 5 is a block diagram illustrating an electrical
configuration of the clearer;
7
FIG. 6 is a graph illustrating an example of a
transition of the detection value until the yarn is
introduced to the detection region;
FIG. 7 is a graph illustrating an example of a
5 transition of the detection value when the foreign
substances enter before the yarn is introduced to the
detection region;
FIG. 8 is a graph illustrating an example of a
transition of the detection value when the foreign
10 substances enter before the yarn is introduced to the
detection region but the foreign substances immediately
separated;
FIG. 9 is a graph for describing a process when the
detection value is greatly increased by the influence of
15 the temperature drift;
FIG. 10 is a graph illustrating an example of a
transition of the detection value when the foreign
substances enter the detection region but the foreign
substances separated before the yarn is introduced;
20 FIG. 11 is a flowchart illustrating a process carried
out by a clearer control section; and
FIG. 12 is a graph illustrating an alternative
embodiment in which a foreign substance determination range
is fixedly defined.
25
DETAILED DESCRIPTION OF PREFERED EMBODIMENTS
Embodiments of the present invention will be
hereinafter described with reference to the drawings. FIG.
1 is a schematic side view of a yarn winding unit 1 arranged
30 in a yarn winding machine according to an embodiment of the
present invention.
8
The yarn winding machine of the present embodiment
has a configuration in which a plurality of yarn winding
units 1 are arranged in a row. The yarn winding machine
includes a machine management device (not illustrated) that
5 intensively manages the yarn winding unit 1.
The yarn winding unit 1 illustrated in FIG. 1 is
configured to wind a yarn 10 supplied from a yarn supplying
section (not illustrated) around a winding bobbin to form
a package 20. The configuration drawn in the figure shows
10 a common portion for describing two cases, when the yarn
winding unit 1 is a spinning unit of a spinning machine and
when the yarn winding unit 1 is a winding unit of an automatic
winder. When the yarn winding unit 1 is the spinning unit
of the spinning machine, for example, the pneumatic
15 spinning device corresponds to the yarn supplying section.
When the yarn winding unit 1 is the winding unit of the
automatic winder, a mechanism adapted to support the yarn
supplying bobbin corresponds to the yarn supplying section.
Each yarn winding unit 1 includes a unit control
20 section 30 configured by a computer. The unit control
section 30 is configured by hardware such as CPU, ROM, and
RAM, and software such as a control program stored in the
ROM and/or the RAM. With the cooperative operation of the
hardware and the software, the unit control section 30
25 controls each component of the yarn winding unit 1. The
unit control section 30 of each yarn winding unit 1 is
configured to be communicable with the machine management
device. Thus, the operation of each yarn winding unit 1
can be intensively managed by the machine management
30 device.
The yarn winding unit 1 includes, in order from
9
upstream in a traveling direction of the yarn 10, an
upstream guide 11, a clearer (yarn monitoring device) 15,
a downstream guide 17, and a winding section 18. When the
yarn winding unit 1 is the spinning unit, a first yarn
5 catching device 12, a second yarn catching device 13, and
a yarn joining device 14 may be arranged for each unit, but
one or a plurality of movable yarn joining carts may be
arranged commonly for a plurality of units, and the first
yarn catching device 12, the second yarn catching device
10 13, and the yarn joining device 14 are preferably arranged
on the yarn joining cart. When the yarn winding unit 1 is
the winding unit, the first yarn catching device 12, the
second yarn catching device 13, and the yarn joining device
14 are preferably arranged for each unit. The yarn joining
15 device 14 is located upstream of the clearer 15.
The upstream guide 11 is arranged downstream of the
yarn supplying section. The upstream guide 11 guides the
yarn 10 fed from the yarn supplying section.
The first yarn catching device 12 is configured to
20 be swingable, as illustrated in FIGS. 1 to 3, when the unit
control section 30 drives a motor (not illustrated). The
first yarn catching device 12 is connected to a negative
pressure source (not illustrated), and can generate a
suction flow at a distal end side (opposite side of the
25 center of swing) of the first yarn catching device 12. The
first yarn catching device 12 is arranged such that the
center of swing is located upstream of the yarn joining
device 14.
The second yarn catching device 13 is configured to
30 be swingable, similarly to the first yarn catching device
12, when the unit control section 30 drives a motor (not
10
illustrated). The second yarn catching device 13 is
connected to a negative pressure source (not illustrated),
and can generate a suction flow at a distal end side
(opposite side of the center of swing) of the second yarn
5 catching device 13. The second yarn catching device 13 is
arranged such that the center of swing is located downstream
of the yarn joining device 14.
The clearer (yarn monitoring device) 15 monitors the
state (thickness, mixture of foreign substance such as
10 color yarn, polypropylene, and the like) of the travelling
yarn 10, and detects a yarn defect (portion with abnormality
in yarn 10) contained in the yarn 10. The clearer 15 also
includes a cutter (cutting device) 16 adapted to cut the
yarn 10 when the clearer 15 detects the yarn defect. The
15 detailed configuration of the clearer 15 will be described
later.
The downstream guide 17 is arranged slightly
downstream of the clearer 15. The downstream guide 17
guides the yarn 10 fed to the winding section 18.
20 The winding section 18 includes a package supporting
section (not illustrated) and a winding drum 19. The
winding drum 19 is driven while making contact with the
outer peripheral surface of the winding bobbin 21 or the
package 20. The winding section 18 drives the winding drum
25 19 with a motor (not illustrated) and winds the yarn 10 while
traversing the yarn 10 while rotating the package 20 making
contact with the winding drum 19 to form the package 20.
The method for carrying out the traversing is
arbitrary, and the traverse device may be individually
30 arranged for each yarn winding unit 1 or one traverse device
may traverse the yarn 10 of a plurality of yarn winding units
11
1. The traverse device individually arranged for each yarn
winding unit 1 may be a traverse groove formed in the winding
drum 19 or an arm type traverse device. The arm type
traverse device is preferably applied to a structure of
5 directly driving the winding bobbin 21 with a motor (not
illustrated).
The yarn winding unit 1 is configured as above, so
that the yarn 10 supplied from the yarn supplying section
can be wound while being traversed with the winding section
10 18 to form the package 20.
If the yarn 10 between the yarn supplying section and
the winding section 18 is disconnected for some reason, the
first yarn catching device 12, the second yarn catching
device 13, the yarn joining device 14, and the like
15 cooperatively operate to carry out a series of steps for
the yarn joining operation to bring the yarn 10 in the
connected state again.
This step will be described below. When the yarn 10
is disconnected, the winding section 18 first immediately
20 stops the winding if the winding section 18 is in winding.
Then, as illustrated in FIG. 2, the first yarn catching
device 12 is swung towards the yarn supplying section to
suck and catch the yarn end from the yarn supplying section.
At substantially the same time, the second yarn catching
25 device 13 is swung towards the winding section 18 to suck
and catch the yarn end from the winding section 18.
Thereafter, the first yarn catching device 12 and the
second yarn catching device 13 are respectively swung to
return to the standby positions while sucking the yarn ends.
30 Thus, as illustrated in FIG. 3, the yarn end from the yarn
supplying section and the yarn end from the winding section
12
18 are supplied to the yarn joining device 14. Furthermore,
the yarn 10 is set in the clearer 15 at substantially the
same timing as the guiding of the yarn ends, and the yarn
10 is detected by the clearer 15.
5 The yarn joining device 14 is configured as a
pneumatic splicer that acts a whirling airflow on the yarn
end from the yarn supplying section and the yarn end from
the winding section 18 to twist and connect the two yarn
ends. The yarn joining device 14 is not limited thereto,
10 and for example, may be a mechanical knotter.
According to the above-described steps, the yarn 10
in the disconnected state can be joined in the yarn joining
device 14 to be in the connected state. The series of steps
for the yarn joining operation are repeated each time the
15 yarn 10 is disconnected. Therefore, the above-described
series of steps is sometimes referred to as a yarn joining
cycle.
The yarn joining cycle is realized such that the unit
control section 30 controls the first yarn catching device
20 12, the second yarn catching device 13, the yarn joining
device 14, and the like to operate at an appropriate timing.
The setting operation of the yarn 10 in the clearer
15 is carried out at the timing the yarn end is guided to
the yarn joining device 14 (i.e., immediately before the
25 yarn joining operation by the yarn joining device 14), the
timing before the winding is resumed after the doffing, and
the like. The unit control section 30 determines whether
or not the yarn 10 is normally set in the clearer 15 in the
yarn joining cycle based on whether or not an appropriate
30 signal (specifically, yarn presence signal, to be described
later) from the clearer 15 is input to the unit control
13
section 30. If the yarn presence signal from the clearer
15 is not input to the unit control section 30, which means
that the yarn 10 cannot be monitored with the clearer 15,
the unit control section 30 assumes that the yarn joining
5 cycle failed, cancels the yarn joining operation by the yarn
joining device 14, and carries out the series of steps over
again from the beginning.
When the yarn 10 of a predetermined length is wound
around the winding bobbin 21 and the package 20 is fully
10 wound, the yarn 10 is automatically cut by the cutter 16
of the clearer 15, and the winding of the winding section
18 is stopped. Thereafter, the package 20 is detached from
the winding section 18 by a manual operation of an operator,
and an empty winding bobbin 21 is attached to the winding
15 section 18 instead of the package 20, and the winding is
resumed. The doffing operation may not be a manual
operation and may be carried out with a known automatic
doffing device.
Next, a description will now be made on a
20 configuration of the clearer 15 with reference to FIG. 4.
FIG. 4 is a perspective view illustrating a configuration
of the clearer 15.
As illustrated in FIG. 4, the clearer 15 of the present
embodiment includes an optical sensor unit (detecting
25 section) 35 capable of measuring the state of the yarn 10.
The sensor unit 35 includes a housing 37.
The housing 37 is formed with a slit-shaped recess
38, and the yarn 10 can travel inside the recess 38. The
recess 38 is formed as a linear groove with one side opened,
30 and the detection region 36 is located inside the recess
38. The detection region 36 is a region where the light
14
from the light projecting section 41 is projected, and is
a region where the yarn 10 can be detected according to the
light receiving amount of the light receiving section 42,
to be described later.
5 The clearer 15 includes the cutter 16, as described
above, and is arranged such that the cutting blade of the
cutter 16 emerges (advances/retracts) on the upstream side
in the yarn travelling direction of the detection region
36 in the recess 38.
10 The yarn path guides 131, 132 for guiding the yarn
10 travelling through the recess 38 are attached to the
housing 37. A display lamp (notifying device,
illumination device) 46 is installed on the housing 37, so
that the status of the clearer 15 can be indicated and the
15 abnormality can be notified to the operator by the lighting
state of the display lamp 46.
Furthermore, a display (notifying device, display
device) 47 is installed on the housing 37. The display 47
is configured as a liquid crystal display, for example, and
20 can display characters, symbols, figures, and the like, as
needed. Therefore, the display 47 can notify the operator
of the information related to the operation state of the
clearer 15 more specifically than the display lamp 46. For
example, when abnormality occurs in the clearer 15, the
25 abnormality can be notified to the operator by displaying
a warning screen.
Two blow-out ports, that is, a first blow-out port
151 and a second blow-out port 152 that can eject compressed
air are formed in the housing 37.
30 The first blow-out port 151 is formed into a circular
hole shape in the inner wall on the far side of the recess
15
38. When the air is ejected from the first blow-out port
151, the flow of air along the side wall of the recess 38
is generated, and the air can be blown against the detection
region 36 and the vicinity of the cutting blade of the cutter
5 16.
The second blow-out port 152 is formed to a slit-shape
and is arranged exterior to the recess 38. The second
blow-out port 152 is inclined with respect to the direction
of the arrow in FIG. 4, that is, the width direction of the
10 groove-shaped recess 38, and can blow air into the recess
38 in the direction diagonal to the yarn travelling
direction. The air ejected from the second blow-out port
152 is blown to the inside from the open side and the yarn
travelling upstream side of the recess 38 and diagonally
15 hits the side wall on one side of the recess 38, thus
generating a spiral-shaped airflow in the recess 38 and
blowing air to the detection region 36, and the like.
Thus, even if the foreign substances such as the fiber
waste enter the recess 38 (detection region 36), the foreign
20 substances can be blown away and removed to the outside of
the recess 38 by ejecting air from the first blow-out port
151 and the second blow-out port 152.
Next, a description will now be made on a
configuration of the clearer 15 with reference to FIG. 5.
25 FIG. 5 is a block diagram illustrating an electrical
configuration of the clearer 15.
As illustrated in FIG. 5, the clearer 15 includes the
sensor unit 35 and a clearer control section (control
section) 50. The sensor unit 35 includes a drive circuit
30 40, the light projecting section 41, the light receiving
section 42, an amplifier 43, a high-pass filter 44, an
16
amplifier circuit 45, the display lamp 46, the display 47,
the cutter 16, and a compressed air electromagnetic valve
48.
The light projecting section 41 includes a light
5 emitting element configured by a light emitting diode (LED).
The light projecting section 41 irradiates the yarn 10
travelling through the yarn path with light at a light
amount corresponding to a drive voltage input from the drive
circuit 40. The drive voltage generated by the drive
10 circuit 40 is determined based on an electrical signal input
from a DA converter 52 arranged in a clearer control section
50.
The light receiving section 42 is arranged on the
opposite side of the light projecting section 41 with the
15 recess 38 in between (i.e., with the yarn path passing
through the recess 38 in between). The light receiving
section 42 includes a light receiving element configured
by a photodiode and the like. The light receiving section
42 receives a transmitted light of the light radiated from
20 the light projecting section 41 to the yarn 10, and outputs
the electrical signal (voltage) corresponding to the light
receiving amount. The electrical signal changes depending
on the shape (cross-sectional shape) of the yarn 10 existing
between the light projecting section 41 and the light
25 receiving section 42.
The electrical signal output by the light receiving
section 42 is amplified by the amplifier 43, and thereafter,
a signal of a predetermined high frequency is extracted with
the high-pass filter 44, and again amplified with the
30 amplifier circuit 45. Since the inverting process is
carried out in the amplifier 43 of the present embodiment,
17
the electrical signal output by the amplifier 43 is small
as the light receiving amount of the light receiving section
42 increases. The amplified electrical signal is output
as a detection value from the sensor unit 35, and converted
5 to a digital signal by an AD converter 51 of the clearer
control section 50.
The display lamp 46 can indicate the operation state
of the clearer 15 to the operator by being turned ON and
turned OFF. In the present embodiment, the display lamp
10 46 is configured as a so-called two color LED, and can be
lighted in green and red. The lighting state of the display
lamp 46 is controlled by the clearer control section 50.
Therefore, the display 47 can notify the operator of
the information related to the operation state and the like
15 of the clearer 15 by displaying characters, symbols,
figures, and the like. The display content of the display
47 is controlled by the clearer control section 50.
The cutter 16 includes the cutting blade, as
described above, and the cutting blade is driven by a
20 solenoid, for example. The cutter 16 is electrically
connected to the clearer control section 50, and is
configured to cut the yarn 10 on the basis of a cutting signal
output by the clearer control section 50.
The compressed air electromagnetic valve 48 is
25 arranged on a path between the supplying source (e.g.,
blower of yarn winding machine) of the compressed air (not
illustrated) and the first blow-out port 151 and the second
blow-out port 152 described above. The compressed air
electromagnetic valve 48 is electrically connected to the
30 clearer control section 50, and is opened for a
predetermined time based on an injection signal output by
18
the clearer control section 50 to inject air from the first
blow-out port 151 and the second blow-out port 152. The
first blow-out port 151, the second blow-out port 152, and
the compressed air electromagnetic valve 48 configure a
5 foreign substance removing device adapted to remove foreign
substances from the detection region 36.
In the present embodiment, the clearer control
section 50 carries out the control to open the compressed
air electromagnetic valve 48 to inject the air from the
10 first blow-out port 151 and the second blow-out port 152
immediately after the unit control section 30 starts the
yarn joining cycle. At the beginning of the yarn joining
cycle, the yarn 10 is not introduced to the detection region
36, and thus the air is injected at such timing to prevent
15 the yarn 10 from inhibiting the flow of air. Therefore,
the foreign substances existing in the detection region 36
can be effectively blown away and removed.
The clearer control section 50 stores, in the storage
section 57, to be described later, an evaluation reference
20 value which is obtained from the detection value output by
the sensor unit 35 when the yarn 10 does not exist in the
detection region 36. The yarn state evaluating section 53
arranged in the clearer control section 50 compares the
evaluation reference value and the detection value to
25 evaluate (measure) the state of the yarn 10.
Next, a description will now be made on an electrical
configuration of the clearer control section 50. The
clearer control section 50 includes the yarn state
evaluating section (evaluating section) 53, an adjusting
30 section (light projection adjusting section) 54, an
acquiring section 55, a yarn presence/absence determining
19
section 56, a data storage section 57, a setting section
58, and a foreign substance responding processing section
59. Specifically, the clearer control section 50 is
configured as a computer including hardware such as CPU,
5 ROM, and RAM, and software such as a control program is
stored in the ROM. With the cooperative operation of the
hardware and the software, the clearer control section 50
can operate as the yarn state evaluating section 53, the
adjusting section 54, the acquiring section 55, the yarn
10 presence/absence determining section 56, the data storage
section 57, the setting section 58, the foreign substance
responding processing section 59, and the like.
After the yarn joining cycle is started and the air
is injected from the first blow-out port 151 and the second
15 blow-out port 152, the adjusting section 54 carries out the
adjusting process (the light projection adjusting process)
after a lapse of a short time. The adjusting process is
a process of adjusting a drive voltage which is applied to
the light projecting section 41 in the sensor unit 35 such
20 that the detection value (specifically, the output voltage)
output by the sensor unit 35 becomes a predetermined
adjustment reference value in the state where the yarn 10
does not exist in the detection region 36 of the clearer
15.
25 The acquiring section 55 performs the measuring
process. The measuring process is a process of controlling
the sensor unit 35 so that the voltage adjusted by the
adjusting process is applied to the light projecting
section 41, and acquiring the detection value actually
30 output by the sensor unit 35 in the state where the yarn
10 does not exist in the detection region 36 of the clearer
20
15. The detection value (specifically, the output voltage
of the sensor unit 35) obtained in such a manner is assumed
to be a value which is substantially the same as the
adjustment reference value in the adjusting process, but
5 may be a diverged value due to, for example, the influence
of temperature drift, entering and separation of fiber
waste (foreign substances), and the like. The detection
value acquired by the acquiring section 55 is stored in the
data storage section 57, to be described later.
10 The yarn presence/absence determining section 56
determines whether or not the yarn 10 exists in the
detection region 36 (particularly, a yarn path in the
detection region 36) of the clearer 15 and whether or not
the yarn 10 is introduced to the detection region 36
15 (particularly, a yarn path in the detection region 36) based
on the detection value acquired by the acquiring section
55. Specifically, the yarn presence/absence determining
section 56 determines that the yarn 10 exists in the yarn
path (yarn is present) if the output voltage of the sensor
20 unit 35 is greater than or equal to a predetermined
threshold value (yarn presence/absence determination
threshold value), and determines that the yarn 10 does not
exist in the yarn path (yarn absent) if the output voltage
is not greater than or equal to the predetermined threshold
25 value. The detection region 36 is a space having a
predetermined size. The yarn path in the detection region
36 can be represented as a position where the yarn 10 travels,
the position being regulated with a pair of upper and lower
yarn path guides 131, 132 (position of one point in a plan
30 view: a predetermined position).
If it is determined that yarn is present, the yarn
21
presence/absence determining section 56 (clearer control
section 50) outputs, to the unit control section 30, a
signal notifying that the yarn is present (yarn presence
signal). The unit control section 30 determines whether
5 or not the yarn 10 is normally set in the detection region
36 by the yarn joining cycle using whether or not the yarn
presence signal is input from the clearer control section
50. However, the output of the yarn presence signal of the
yarn presence/absence determining section 56 may not be
10 carried out, and details thereof will be described later.
The data storage section 57 has a storage region where
the content can be updated, and for example, is realized
by a rewritable volatile or non-volatile memory (e.g., RAM
and EEPROM) and the like. The data storage section 57 can
15 store various parameters and the like for controlling the
clearer 15.
Specifically, the data storage section 57 can store
a plurality of measurement values obtained by the acquiring
section 55. In other words, the acquiring section 55
20 repeatedly performs, over a plurality of times, the
measuring process for each predetermined time interval
until the yarn 10 is introduced to the yarn path in the
detection region 36 of the clearer 15 (position of the yarn
10 is within in the yarn path: positioning) instead of
25 performing the measuring process only once, and acquires
the detection value each time. The data storage section
57 can store the data of the detection value for a
predetermined number of times in the order of time series
as a candidate value of the evaluation reference value, to
30 be described later.
The data storage section 57 can store therein a
22
foreign substance determination range defined to detect
entering and separation of the fiber waste and the like
(foreign substances) with respect to the detection region,
and a reference value that is a reference of the foreign
5 substance determination range when the yarn 10 exists in
the detection region 36 of the clearer 15. The foreign
substance determination range and the like will be
described in detail with reference to the graph of FIG. 6
and the like.
10 Furthermore, the data storage section 57 can store
an upper limit value and a lower limit value of a normal
range indicating a range the detection value normally takes
when the yarn 10 does not exist in the detection region 36
of the clearer 15. The upper limit value and the lower limit
15 value of the normal range are threshold values set in
advance, and the normal range is defined by the threshold
values. The normal range is defined such that the width
becomes wider than the width of the foreign substance
determination range.
20 Furthermore, the data storage section 57 can store
the yarn presence/absence determination threshold value
which is the threshold value used as a boundary for the yarn
presence/absence determining section 56 to determine the
presence/absence of the yarn 10. A value greater than the
25 upper limit value of the normal range is set for the yarn
presence/absence determination threshold value.
The data storage section 57 can also store a set value
of the evaluation reference value determined by the setting
section 58, to be described later. The yarn state
30 evaluating section 53 evaluates the state of the yarn 10
by comparing with the evaluation reference value.
23
Specifically, an average value of the difference between
the voltage set as the evaluation reference value and the
voltage obtained from the sensor unit 35 with the yarn 10
in the detection region 36 of the clearer 15 is used for
5 the monitoring of the yarn 10 (e.g., calculation of the
average thickness of the yarn 10).
The setting section 58 determines (calculates) the
value of the evaluation reference value based on the
detection value satisfying a predetermined condition of the
10 detection values (the candidate value of evaluation
reference value) obtained by the acquiring section 55 and
stored in the storage section 57, and stores the result in
the data storage section 57 as a new set value. In the
present embodiment, storing the new set value of the
15 evaluation reference value over again in the data storage
section 57 is called “reference correction”.
Next, a description will be made on two factors that
lower the yarn evaluation accuracy (yarn monitoring
accuracy) of the sensor unit 35 of the present embodiment.
20 One of the two factors is the change in environment
represented by the temperature drift, and the like of the
LED adopted by the light projecting section 41, and the
other remaining factor is the foreign substance entering
the detection region 36.
25 The details will be described later. As illustrated
in the present embodiment, the following preparing
operation is generally carried out before the start of
evaluation of the yarn 10 in the clearer 15 including the
adjusting section 54, the acquiring section 55, and the
30 setting section 58. In other words, in the state where the
yarn 10 does not exist in the detection region 36, the
24
adjusting section 54 first correctly adjusts the light
projecting amount of the light projecting section 41 of the
sensor unit 35 by the adjusting process. Then, the
acquiring section 55 acquires the detection value of the
5 sensor unit 35, and the setting section 58 sets the
evaluation reference value based on the detection value in
the state where the yarn 10 does not exist in the detection
region 36.
After the preparing operation is completed, the yarn
10 10 is introduced to the detection region 36, the yarn
winding unit 1 starts the winding, and the state of the yarn
10 is evaluated by the yarn state evaluating section 53.
In this case, the light projecting section 41 is driven with
a drive voltage just adjusted in the preparing operation,
15 and an evaluation reference value set in the preparing
operation is used for the reference of evaluation of the
yarn 10. With the above control, the accuracy when
evaluating the state of the yarn 10 can be enhanced.
However, the environment such as temperature and
20 humidity may change from the time the adjusting process is
carried out and the evaluation reference value is set, until
the yarn 10 is actually introduced to the detection region
36. In particular, the clearer 15 of the present embodiment
is optical, and the light projecting section 41 is
25 configured by the LED. Therefore, for example,
immediately after the power is turned ON in the clearer 15,
the temperature of the LED may rise from the time point the
adjusting process is carried out and the evaluation
reference value is set up to the time point the yarn 10 is
30 introduced to the detection region 36, and the light amount
radiated from the light projecting section 41 may change
25
by such a temperature drift (heat drift) of the LED.
Even when the adjusting process is carried out and
the evaluation reference value is set again, if the light
amount of the light projecting section 41 is changed from
5 such setting until the yarn 10 is introduced to the
detection region 36, an error occurs in the evaluation of
the state of the yarn 10 by such an amount, and thus is not
preferable. Thus, it is assumed that the acquisition of
the detection value for defining the evaluation reference
10 value is carried out not immediately after the adjusting
process, but at the timing immediately before introducing
the yarn 10 to the detection region 36. The influence of
the temperature drift and the like thus can be reduced, and
the accurate yarn evaluation can be carried out.
15 However, even if the timing of determining the
evaluation reference value is devised to reduce the
influence of the temperature drift and the like, this cannot
be regarded as sufficient. In other words, the possibility
of the foreign substances such as the fiber waste generated
20 in the yarn winding machine entering the detection region
36 needs to be taken into consideration.
For example, when the foreign substances enter the
detection region 36 after the adjusting process is carried
out, the detection value output by the sensor unit 35 after
25 the entering of the foreign substance is affected by the
foreign substance, and thus the state of the yarn 10 cannot
be accurately evaluated. When the adjusting process is
carried out in the state where the foreign substances
already have entered the detection region 36, the detection
30 value of the sensor unit 35 is affected if the foreign
substances separate from the detection region 36 thereafter,
26
and thus the state of the yarn 10 cannot be accurately
evaluated.
With this regards, in the clearer 15 of the present
embodiment, the entering of foreign substances to the
5 detection region 36 and the separation of the entered
foreign substances from the detection region 36 are
detected from when the adjusting process is carried out
until when the yarn 10 is introduced to the detection region
36 to carry out various types of processing (hereinafter
10 also referred to as foreign substance responding process).
When the foreign substances enter the detection
region 36 or when the foreign substances separate from the
detection region 36, the detection value relatively
drastically varies. When the light amount of the light
15 projecting section 41 lowers by the temperature drift, the
detection value relatively gradually varies. The clearer
15 of the present embodiment uses this fact to clearly
distinguish the change (entering/separation) in the
entering state of the foreign substance from the
20 temperature drift and detect the change
(entering/separation) in the entering state of the foreign
substance.
Now, a description will be made, in detail, on the
control of the clearer control section 50 of the present
25 embodiment in various cases with references to the graphs
of FIGS. 6 to 10.
As described above, after the adjusting section 54
carries out the adjusting process, the acquiring section
55 iteratively acquires the detection value at appropriate
30 time intervals until the introduction of the yarn 10 to the
yarn path of the detection region 36 is detected. In the
27
graph of FIG. 6, the horizontal axis indicates the time,
the vertical axis indicates the detection value, and the
detection values acquired at each timing from t1 to t25 are
illustrated. Furthermore, the graph of FIG. 6 illustrates
5 the foreign substance determination range, the normal range,
and the yarn presence/absence determination threshold
value.
The acquiring section 55 repeats the acquisition of
the detection value at a timing of t1, a timing of t2, and
10 the like. The obtained detection values are sequentially
stored in the data storage section 57 as candidate values
of the evaluation reference value.
At t1, which is the first acquiring timing after the
adjusting process is completed, the acquired detection
15 value is stored in the data storage section 57 as a reference
value defining the foreign substance determination range,
to be described later.
The foreign substance responding processing section
59 sets the foreign substance determination range, which
20 is the range the detection value to be acquired next (the
timing of t2) is to fall within, based on the reference value.
The foreign substance determination range is a range set
to detect the entering of the foreign substances to the
detection region 36 and the separation of the foreign
25 substances from the detection region 36, and is defined with
the above-described reference value as a central value.
When the acquiring section 55 acquires the detection
value at the timing t2, the foreign substance responding
processing section 59 determines whether or not the
30 detection value obtained this time falls within the foreign
substance determination range. In the example of FIG. 6,
28
the detection value at the timing of t2 is greater than or
equal to the lower limit value and smaller than or equal
to the upper limit value of the foreign substance
determination range having the detection value (reference
5 value) at the timing of t1 as a reference. Therefore, the
foreign substance responding processing section 59 then
stores again the detection value at the timing of t2 in the
data storage section 57 as a reference value, sets the
foreign substance determination range based on the new
10 reference value again, and determines whether or not the
detection value at the timing of t3 is within the foreign
substance determination range. The above determination
processes are iterated for a timing of t4, a timing of t5,
and the like, and accordingly the foreign substance
15 determination range is also sequentially updated.
In addition to the determination based on the foreign
substance determination range, other determinations are
also made with respect to the individual detection values.
Specifically, the adjusting section 54 determines whether
20 or not the detection value is within a normal range defined
in advance as a range the detection value usually takes in
the state where the yarn 10 does not exist in the detection
region 36 with respect to the detection value acquired at
each timing. The yarn presence/absence determining
25 section 56 determines whether the detection value is
greater than or equal to a predetermined yarn
presence/absence determination threshold value with
respect to the detection value acquired at each timing. The
above-described normal range is usually set to internally
30 include the foreign substance determination range, but the
foreign substance determination range may be out of the
29
normal range. The yarn presence/absence determination
threshold value is set to a value outside the foreign
substance determination range.
The yarn 10 is eventually introduced to the detection
5 region 36, so that the detection value acquired by the
acquiring section 55 greatly increases at a timing of t25.
Since the detection value obtained at the timing of t25 is
greater than the yarn presence/absence determination
threshold value, the yarn presence/absence determining
10 section 56 determines that the yarn 10 is introduced to the
detection region 36 (yarn is present). In this case, the
setting section 58 sets the detection value (in the example
of FIG. 6, the detection value at a timing of t24) acquired
immediately before the time point, at which determination
15 is made that yarn is present, as the evaluation reference
value. When the reference correction is carried out as
described above and the traveling of the yarn 10 is started
thereafter, the yarn state evaluating section 53 carries
out the evaluation of the yarn 10 based on the set evaluation
20 reference value.
In the example of FIG. 6, the detection value has a
gradual increasing tendency due to the influence of the
temperature drift of the light projecting section 41
described above, although such an influence is not strong
25 enough to cause the detection value to be out of the normal
range illustrated in FIG. 6. With the influence, a
divergence of a certain extent is generated between the
detection value at t1, which is the timing immediately after
the adjusting process, and the detection value at t24, which
30 is the timing immediately before determination is made that
yarn is present. With regards to this, the setting section
30
58 of the present embodiment uses the detection value at
the timing of t24 close to the timing determination is made
that yarn is present as the evaluation reference value, and
thus the influence of the temperature drift can be reduced
5 and the yarn 10 can be accurately evaluated by the yarn state
evaluating section 53.
However, the evaluation reference value is not
limited to the detection value at the timing of t24. For
example, the detection value at the time point at which a
10 predetermined margin back from the time point at which
determination is made that the yarn is present may be used
as the evaluation reference value, or an average value may
be calculated based on a plurality of detection values and
used as the evaluation reference value.
15 Next, a description will be made on a case in which
the detection value transitions as in FIG. 7. In the
example of FIG. 7, the detection values at the timing of
t1 to t3 hardly vary, but as a result of the foreign
substances entering the detection region 36 from t3 to t4,
20 the detection value at the timing of t4 increases less
sharply and becomes greater than the upper limit value of
the foreign substance determination range based on the
detection value (reference value) at the timing of t3.
Similarly to FIG. 6, in the case of FIG. 7 as well,
25 the acquiring section 55 repeats the acquisition of the
detection values of the timing of t1, the timing of t2, and
the like and sequentially stores the obtained detection
values in the data storage section 57 as candidate values
of the evaluation reference value. The update of the
30 reference value and the foreign substance determination
range is carried out similarly to the case of FIG. 6.
31
Since the detection value at the timing of t4 is
greater than the upper limit value of the foreign substance
determination range, the foreign substance responding
processing section 59 stops the update of the reference
5 value and the foreign substance determination range.
Therefore, it is determined whether the detection value at
the next timing t5 is within the foreign substance
determination range having the detection value (reference
value) at the timing of t3, and not t4, as a reference.
10 If the detection value is outside the foreign
substance determination range as in the timing of t4, the
detection value is not stored in the data storage section
57 as the candidate value of the evaluation reference value,
and thus is not be used as the evaluation reference value
15 in the future. Therefore, the suddenly changed irregular
detection value can be reliably prevented from being
adopted as the evaluation reference value.
As the foreign substance continues to remain in the
detection region 36, the detection value at the timing of
20 t5 does not greatly change from the detection value of t4,
and is greater than the upper limit value of the foreign
substance determination range based on the detection value
(reference value) at the timing of t3, and the detection
values at the timing of t6, the timing of t7, and the
25 subsequent timing are also greater than the upper limit
value. At the timing of t22 at which such a state is
continued for a predetermined time (foreign substance
determination time), the foreign substance responding
processing section 59 determines that the foreign
30 substances have entered the detection region 36 (high
probability that the accuracy of yarn evaluation is lowered
32
by the influence of foreign substance).
Thereafter, the yarn 10 is introduced to the
detection region 36, and the detection value is greatly
increased to be greater than or equal to the yarn
5 presence/absence determination threshold value at the
timing of t25, similarly to the case of FIG. 6. The yarn
presence/absence determining section 56 determines that
the yarn is present, but the foreign substance responding
processing section 59, which determines that foreign
10 substance has entered, inhibits the yarn presence/absence
determining section 56 from outputting the yarn presence
signal. As a result, the yarn presence/absence
determining section 56 (clearer control section 50) does
not output the yarn presence signal.
15 The unit control section 30 that swung the first yarn
catching device 12 and the second yarn catching device 13
from the state of FIG. 1 to the state of FIG. 3 is configured
to check that the yarn 10 is introduced to the detection
region 36 of the clearer 15 based on the yarn presence signal
20 from the clearer control section 50. Even if the yarn 10
is actually introduced to the detection region 36, the
foreign substance responding processing section 59 does not
cause the yarn presence/absence determining section 56 to
output the yarn presence signal (i.e., clearer control
25 section 50 operates such that the yarn 10 is not introduced
to detection region 36).
Since the yarn presence signal is not input from the
clearer control section 50 even after waiting for a
predetermined time, the unit control section 30 determines
30 that the introduction of the yarn 10 with respect to the
detection region 36 of the clearer 15 fails such as miscatch
33
of the yarn 10 by the first yarn catching device 12 and the
second yarn catching device 13. Therefore, the unit
control section 30 cancels the operation without carrying
out the yarn joining operation by the yarn joining device
5 14, once returns the first yarn catching device 12 and
second yarn catching device 13 to the state of FIG. 1, and
carries out the yarn joining cycle over again. Thus, the
clearer 15 can avoid the winding of the yarn 10 from starting
in a state where the clearer 15 cannot accurately carry out
10 the yarn evaluation under the influence of the foreign
substances.
At the beginning of the yarn joining cycle carried
out anew, the clearer control section 50 drives the
compressed air electromagnetic valve 48 and the process
15 (foreign substance removing process) of injecting air from
the first blow-out port 151 and the second blow-out port
152 is carried out. Therefore, the foreign substances that
enter the detection region 36 have a high possibility of
being blown away by air, and thus it is expected that the
20 foreign substances do not adversely affect the next
adjusting process and the setting of the evaluation
reference value.
After the air is injected to remove the foreign
substances from the detection region 36, in the clearer
25 control section 50, the adjusting section 54 carries out
the adjusting process again, and thereafter, the acquiring
section 55 iteratively acquires the detection value of the
sensor unit 35 again. If the detection value transitions
as in FIG. 6 and the yarn 10 is introduced to the detection
30 region 36 in this case, the evaluation reference value is
defined as described above, and the yarn state evaluating
34
section 53 evaluates the yarn 10 using such an evaluation
reference value.
Accordingly, in the clearer 15 of the present
embodiment, when determining that the foreign substances
5 have entered the detection region 36 based on the behavior
of the detection value output by the sensor unit 35, the
foreign substance responding processing section 59 carries
out the process (foreign substance responding process) of
inhibiting the yarn presence/absence determining section
10 56 from outputting the yarn presence signal involved in the
determination that the yarn is present. As a result, the
yarn joining cycle is carried out again, and accordingly,
the cleaning of the detection region 36 by the ejection of
air from the first blow-out port 151 and the second blow-out
15 port 152, and the readjustment of the light projecting
amount by the adjusting section 54 are carried out
(therefore, reference correction is also carried out
again).
Therefore, it can be said that the foreign substance
20 responding processing section 59 is substantially carrying
out the removal of the foreign substances by the ejection
of air from the first blow-out port 151 and the second
blow-out port 152, and the readjustment of the light
projecting amount. As a result, the adverse affect by the
25 foreign substances in the adjustment of the light
projecting amount and the reference correction can be
satisfactorily prevented, and the yarn state evaluating
section 53 can accurately evaluate the state of the yarn
10.
30 Next, a description will be made on a case in which
the detection value transitions as in FIG. 8. In the
35
example of FIG. 8, the detection value at the timing of t4
increases less sharply, and the detection value at the
timing of t5 is substantially the same as that at the timing
of t4, but the detection value at the timing of t6 is reduced
5 to a value substantially the same as t3. This indicates
that the foreign substances enter the detection region 36
between t3 and t4, but the foreign substances separate
between t5 and t6 without staying for a long time.
Describing the transition of the detection values in
10 relation with the foreign substance determination range,
the detection value at the timing of t4 is greater and the
detection value at the timing of t5 is also similarly
greater than the upper limit value of the foreign substance
determination range defined with the detection value at the
15 timing of t3 as the reference, but the detection value at
the timing of t6 is greater than or equal to the lower limit
value and smaller than or equal to the upper limit value
of the foreign substance determination range. In other
words, the time during which the upper limit value of the
20 foreign substance determination range is continuously
being exceeded is shorter than the foreign substance
determination time (see FIG. 7). Therefore, in this case,
the foreign substance responding processing section 59 does
not determine that the foreign substances enter (high
25 possibility that the accuracy of the yarn evaluation is
lowered by the influence of foreign substances).
As described above, the detection value at the timing
of t6 is greater than or equal to the lower limit value and
smaller than or equal to the upper limit value of the foreign
30 substance determination range having the detection value
(reference value) at the timing of t3 as a reference.
36
Therefore, the foreign substance responding processing
section 59 sets the detection value at the timing of t6 as
a new reference value, newly re-defines the foreign
substance determination range such that the reference value
5 becomes a reference, and updates the storage content of the
data storage section 57 related to the reference value and
the foreign substance determination range. The detection
values at the timings of t4 and t5 are outside the foreign
substance determination range, and thus are not stored in
10 the data storage section 57 as candidate values of the
evaluation reference value, but the detection value is
stored in the data storage section 57 at the timing of t6
when the detection value is again within the foreign
substance determination range. Thereafter, the foreign
15 substance responding processing section 59 monitors
whether there is a sharp fluctuation (i.e., fluctuation of
going out of the foreign substance determination range) of
the detection value again.
In the example of FIG. 8, the detection value does
20 not greatly vary after the timing of t6 until the yarn 10
is introduced to the detection region 36. When the yarn
10 is introduced to the detection region 36, and the
detection value is greatly increased to be greater than or
equal to the yarn presence/absence determination threshold
25 value at the timing of t25, the yarn presence/absence
determining section 56 determines that the yarn is present.
Since the foreign substance responding processing section
59 does not determine that the foreign substances have
entered, the yarn presence/absence determining section 56
30 outputs the yarn presence signal as usual, and the setting
section 58 sets the detection value at the timing of t24
37
as the evaluation reference value. Thereafter, with the
start of winding of the yarn 10, the yarn state evaluating
section 53 monitors the yarn 10.
Thus, when the foreign substances once enter the
5 detection region 36 but separate from the detection region
36 in a short time, it is assumed that the foreign substances
have not entered and hence the foreign substance responding
process by the foreign substance responding processing
section 59 is not carried out and the usual process is
10 carried out. Therefore, the useless foreign substance
responding process is prevented from being carried out, and
the efficiency of the yarn winding machine can be enhanced.
The phenomenon in which the detection value once
sharply increases but returns to the original value in a
15 short time as in FIG. 8 may occur due to factors other than
the foreign substances. For example, in the doffing
operation, the doffing operation itself may be normally
carried out, but the detection value of the sensor unit 35
may become very unstable and may be temporarily outside the
20 foreign substance determination range. However, in the
doffing operation, such variation does not continue for a
long period unlike the foreign substance determination time,
and the varied detection value returns to the original value
in a short time in most cases. Therefore, the wasteful
25 foreign substance responding process can be prevented from
being carried out during the normal doffing operation,
which also enhances the efficiency of the yarn winding
machine.
Next, a description will be made on a case in which
30 the detection value transitions as in FIG. 9. The example
of FIG. 9 shows a case in which the influence of the
38
temperature drift of the light projecting section 41 is
strong, and the detection value has a stronger increasing
tendency than the case of FIG. 6 from immediately after the
adjusting process. The amount of increase of the detection
5 value for each time is within the foreign substance
determination range.
The detection value that is increased for each
acquisition eventually becomes greater than the upper limit
value of the normal range. The adjusting section 54
10 detecting that the detection value acquired at the timing
of t19 is greater than the upper limit value of the normal
range again carries out the adjusting process.
Accordingly, the measuring process and the reference
correction are carried out again after the adjusting
15 process is completed.
With the processes described above, when the
unacceptable temperature drift occurs, the adjusting
process may be carried out again by the adjusting section
54. In other words, the state of the yarn 10 may be
20 accurately evaluated while readjusting the drive voltage
of the light projecting section 41 to eliminate the
influence of the temperature drift.
In the example described above, when the detection
value is greater than the upper limit value of the normal
25 range even once, the adjusting process is carried out again.
Alternatively, the adjusting section 54 may carry out the
adjusting process again when the detection value is greater
continuously for a predetermined adjustment determination
time (light projection adjustment determination time). In
30 this case, for example, the wasteful adjusting process can
be prevented from being carried out due to the noise
39
appearing in the detection value.
The increase in the detection value by the
temperature drift as illustrated in FIG. 9 has
characteristics different from the increase in the
5 detection value by the entering of the foreign substances
as illustrated in FIGS. 7 and 8. In other words, when the
detection value is increased by the influence of the
temperature drift, the amount of increase with respect to
the detection value at the previous timing is relatively
10 small and smooth compared to the case in which the foreign
substances enter, and thus the detection value is less
likely to be out of the foreign substance determination
range as long as the time interval for acquiring the
detection value is sufficiently short. In fact, in the
15 example of FIG. 9, the individual detection value until the
detection value becomes greater than the upper limit value
of the normal range at the timing of t19 is not out of the
foreign substance determination range not even once, and
thus the foreign substance responding processing section
20 59 does not determine that the foreign substances have
entered. Thus, the foreign substance responding process
(process of inhibiting output of yarn presence signal) is
not carried out.
Thus, in the present embodiment, when the detection
25 value once sharply varies and such a state after the
variation continues for a predetermined time, the foreign
substance responding processing section 59 determines that
the entering state of the foreign substances has changed,
and carries out the foreign substance responding process.
30 Therefore, it is possible to prevent the mistaken
determination that the variation occurs not by the
40
influence of the temperature drift, but by the foreign
substances, and carrying out of the wasteful foreign
substance responding process.
Next, a description will be made on a case in which
5 the detection value transitions as in FIG. 10. In the
example of FIG. 10, which is the opposite case to FIG. 7,
the detection value at the timing of t4 is smaller than the
lower limit value of the foreign substance determination
range having the detection value (reference value) at t3
10 as a reference, which situation is continued for a long
period of time. This is assumed because the adjusting
process is carried out with the foreign substances entered
in the detection region 36, and thereafter, the foreign
substances remain in the detection region 36 until the
15 timing of t3 but separat from the detection region 36
between t3 and t4.
In this case, the foreign substance responding
processing section 59 carries out a process substantially
similar to the case of FIG. 7. Specifically, since the
20 detection value at the timing of t4 is smaller than the lower
limit value of the foreign substance determination range
based on the detection value (reference value) at the timing
of t3, the foreign substance responding processing section
59 stops the update of the foreign substance determination
25 range. Therefore, it is determined whether the detection
value at the next timing t5 is within the foreign substance
determination range based on the detection value (reference
value) at the timing of t3.
In the example of FIG. 10, the detection value at the
30 timing of t5 is also smaller than the lower limit value of
the foreign substance determination range based on the
41
detection value at the timing of t3, which state is
continued through the timing of t6, the timing of t7, and
the subsequent timing. The foreign substance responding
processing section 59 determines that the foreign
5 substances have separated from the detection region 36 at
the timing of t22 in which the relevant state continued for
a predetermined time (foreign substance determination
time). Therefore, similarly to the case of FIG. 7, in which
it is determined that the foreign substances have entered,
10 the foreign substance responding processing section 59
inhibits the yarn presence/absence determining section 56
from outputting the yarn presence signal even if the yarn
10 is introduced to the detection region 36, and urges the
yarn joining cycle to be carried out again. Thus, since
15 the adjusting process and the reference correction can be
carried out anew with the foreign substances separated, the
yarn state evaluating section 53 can accurately evaluate
the state of the yarn 10.
Next, a description will be made on a specific process
20 carried out by the adjusting section 54, the acquiring
section 55, the yarn presence/absence determining section
56, the setting section 58, the foreign substance
responding processing section 59, and the like of the
clearer control section 50 with reference to the flowchart
25 of FIG. 11.
The adjusting process, the measuring process, and the
like illustrated in FIG. 11 are carried out, other than at
the power activation of the clearer 15, each time the yarn
10 is disconnected for some reason and disappears from the
30 detection region 36 of the clearer 15, and the
above-described yarn joining operation is carried out. A
42
case where the yarn 10 is disconnected includes a case where
the clearer 15 finds the yarn defect in the yarn monitoring
and cuts the yarn 10 by the cutter 16, a case where the
package 20 is fully wound and the yarn 10 is cut by the cutter
5 16, and a case where the yarn breakage occurs.
Since the adjusting process and the measuring process
are frequently carried out as described above, the yarn 10
can be stably monitored regardless of the change in the
surrounding environment, attachment of contamination to
10 the light projecting section 41, the light receiving
section 42, and the like of the clearer 15, and the like.
Furthermore, as described above, the air from the first
blow-out port 151 and the second blow-out port 152 is
injected at the beginning of the yarn joining cycle, and
15 then the process of FIG. 11 is started, so that the adjusting
process, the measuring process, and the like can be
prevented from being carried out with the foreign
substances entered to the detection region 36.
If the process of FIG. 11 starts without the yarn 10
20 existing in the detection region 36 of the clearer 15, the
adjusting process by the adjusting section 54 is first
carried out, and the drive voltage of the light projecting
section 41 in the sensor unit 35 is adjusted as described
above (step S101). After the adjusting process is
25 completed, a process of initializing a foreign substance
entry change flag to “0” is carried out (step S102).
Immediately thereafter, the iterative acquiring process
(steps S103 to S110) of the detection values by the
acquiring section 55 is started.
30 Specifically, the acquiring section 55 controls the
sensor unit 35 so as to apply the drive voltage adjusted
43
by the adjusting process to the light projecting section
41, and acquires the detection value actually output by the
sensor unit 35 (measuring process described above, step
S103). Thereafter, the yarn presence/absence determining
5 section 56 determines whether or not the detection value
acquired by the acquiring section 55 is greater than or
equal to the yarn presence/absence determination threshold
value (step S104). If the detection value is smaller than
the yarn presence/absence determination threshold value,
10 the adjusting section 54 determines whether the detection
value is within the normal range, that is, whether the
detection value is greater than the lower limit value and
smaller than the upper limit value of the normal range (step
S105). If the detection value is greater than or equal to
15 the upper limit value of the normal range, it is assumed
that an unacceptable temperature drift has occurred, and
the process returns to step S101. As a result, the
adjusting section 54 readjusts the light projecting amount,
and the subsequent processes are carried out again.
20 If the detection value is greater than the lower limit
value and smaller than the upper limit value of the normal
range in the determination of step S105, the foreign
substance responding processing section 59 determines
whether or not the detection value is within the foreign
25 substance determination range defined based on the previous
detection value (reference value) (step S106). If the
detection value is within the foreign substance
determination range (i.e., greater than or equal to the
lower limit value and smaller than or equal to the upper
30 limit value of the foreign substance determination range),
the foreign substance responding processing section 59
44
stores the detection value obtained this time in the data
storage section 57 as a reference value, and newly redefines
the foreign substance determination range based on such a
reference value to store the range in the data storage
5 section 57 (step S107). Furthermore, the acquiring
section 55 stores the detection value obtained this time
in the data storage section 57 separately from the reference
value as a candidate value to be used for the setting of
the evaluation reference value (step S108).
10 If the detection value is outside the foreign
substance determination range (i.e., smaller than the lower
limit value or greater than the upper limit value of the
foreign substance determination range) in the
determination of step S106, the foreign substance
15 responding processing section 59 further determines
whether the state where the detection value is outside the
foreign substance determination range is continued for a
predetermined time (i.e., the foreign substance
determination time) in step S109. If the state where the
20 detection value is outside the foreign substance
determination range is continued for the foreign substance
determination time, the foreign substance responding
processing section 59 determines that entering or
separation of foreign substances has occurred, sets the
25 foreign substance entry change flag to “1” (step S110), and
then returns to step S103. If the time in which the state
of the detection value being outside the foreign substance
determination range is continued is shorter than the
foreign substance determination time in the determination
30 of step S109, the process returns to step S103 while holding
the foreign substance entry change flag at “0” (skip step
45
S110 of setting foreign substance entry change flag to “1”).
If the detection value is greater than or equal to
the yarn presence/absence determination threshold value in
the determination of step S104, the state of the foreign
5 substance entry change flag is examined (step S111). If
the foreign substance entry change flag is “0”, this means
that determination has not been made by the foreign
substance responding processing section 59 that the
entering/separation of foreign substances has occurred.
10 Therefore, in this case, the setting section 58 sets the
evaluation reference value based on the detection value
stored in the data storage section 57 in step S108 by the
acquiring section 55 (step S112). Specifically, among the
plurality of detection values stored in the data storage
15 section 57 in time series order, the setting section 58 sets,
as the evaluation reference value, the latest detection
value acquired immediately before the timing when
determination is made that yarn is present, and the data
storage section 57 stores the latest detection value as the
20 evaluation reference value. Then, the yarn
presence/absence determining section 56 outputs the yarn
presence signal (step S113). The unit control section 30
which receives the yarn presence signal immediately carries
out the yarn joining operation by the yarn joining device
25 14 as necessary, and thereafter, starts the winding of the
yarn 10 by the winding section 18. The yarn state
evaluating section 53 evaluates the yarn 10 travelling
through the detection region 36 based on the value of the
new evaluation reference value (step S114).
30 If the foreign substance entry change flag is “1” in
the determination of step S111, this means that
46
determination has been made by the foreign substance
responding processing section 59 that the
entering/separation of foreign substances has occurred.
Therefore, the foreign substance responding processing
5 section 59 inhibits the yarn presence/absence determining
section 56 from outputting the yarn presence signal, which
is normally output, and stops in such a state (step S115).
As a result, the clearer 15 operates such that the yarn 10
does not exist although the yarn 10 is actually set and is
10 present (located) in the detection region 36. The unit
control section 30 assumes that the introduction of the yarn
10 to the detection region 36 of the clearer 15 fails and
carries out the yarn joining cycle again since the yarn
presence signal is not input even after waiting for a
15 predetermined time. At the beginning of the newly started
yarn joining cycle, the air is injected from the first
blow-out port 151 and the second blow-out port 152, and
hence even if the foreign substances have entered the
detection region 36, the foreign substances can be blown
20 away and removed. Thereafter, the processes illustrated
in the flowchart of FIG. 11 are carried out again from the
beginning.
With the above processes, the yarn state evaluating
section 53 of the clearer control section 50 can
25 satisfactorily eliminate the influence of
entering/separation of foreign substances, and the
influence of temperature drift, and the like of the light
projecting section 41, and can accurately evaluate the
state of the yarn 10.
30 At the time point at which the foreign substance entry
change flag is set to “1” (step S110) or the time point at
47
which the yarn presence/absence determining section 56 is
stopped without outputting the yarn presence signal (step
S115), the display lamp 46 and the display 47 are controlled
to display the occurrence of entering/separation of foreign
5 substances. The abnormality of the detection value caused
by the foreign substances thus can be notified to the
operator in an easily understandable manner.
The flowchart of FIG. 11 illustrates that it is
determined whether or not the detection value is within the
10 foreign substance determination range in step S106, but
actually it is determined whether the detection value is
greater than the upper limit value of the foreign substance
determination range, smaller than the lower limit value of
the foreign substance determination range, or greater than
15 or equal to the lower limit value and smaller than or equal
to the upper limit value of the foreign substance
determination range. If the detection value is greater
than the upper limit value of the foreign substance
determination range, a notice that the foreign substances
20 have entered is displayed on the display 47, and if the
detection value is smaller than the lower limit value of
the foreign substance determination range, a notice that
the foreign substances have separated is displayed on the
display 47. Therefore, whether the abnormality is due to
25 the entering of the foreign substance or the abnormality
is due to the separation of the foreign substance can be
clearly notified to the operator.
The foreign substance responding process carried out
by the foreign substance responding processing section 59
30 in the present embodiment directly inhibits the output of
the yarn presence signal by the yarn presence/absence
48
determining section 56, and the ejection of air from the
first blow-out port 151 and the second blow-out port 152
as well as the readjustment of the light projecting amount
are realized as a result of inhibiting the output of the
5 yarn presence signal (therefore, in the foreign substance
responding process, foreign substance detection signal
like foreign substance entering signal/foreign substance
separating signal is not output). However, even with such
a configuration, it can be recognized that the foreign
10 substance responding processing section 59 substantially
ejects air and readjusts the light projecting amount. Of
course, the foreign substance responding process carried
out by the foreign substance responding processing section
59 (the clearer control section 50) may be a process of
15 outputting, to the compressed air electromagnetic valve 48,
a signal (foreign substance removal request signal) for
ejecting air to the detection region 36. The foreign
substance responding process may include a process of
directly outputting a signal to cause the adjusting section
20 54 to again carry out the adjusting process after removing
the foreign substances.
The foreign substance responding process carried out
by the foreign substance responding processing section 59
may be changed so as to output the foreign substance
25 detection signal in place of or in addition to inhibiting
the output of the yarn presence signal of the yarn
presence/absence determining section 56. For example, the
foreign substance responding processing section 59 may
transmit the foreign substance entering signal/foreign
30 substance separation signal to the unit control section 30,
and the unit control section 30 receiving such a signal may
49
cancel the yarn joining operation by the yarn joining device
14 and carry out the yarn joining cycle again (i.e.,
resuming of winding is inhibited).
The foreign substance responding process carried out
5 by the foreign substance responding processing section 59
may include other various processes, for example, a process
of outputting a winding inhibiting signal of inhibiting the
start of winding of the winding section 18. When the yarn
joining signal requesting for the yarn joining operation
10 is input in the middle of the yarn joining cycle, the unit
control section 30 may be configured to carry out the yarn
joining cycle again from the beginning, and the foreign
substance responding processing section 59 may carry out
the process of outputting the yarn joining signal to the
15 unit control section 30 as the foreign substance responding
process. Thus, various responses can be taken with respect
to the entering/separation of the foreign substances.
As illustrated in FIG. 12, the foreign substance
determination range may be defined to become a fixed range.
20 In the example of the graph of FIG. 12, the foreign substance
determination range is defined to have a predetermined
width with the adjustment reference value in the adjusting
process as a reference. In the alternative embodiment, the
foreign substance determination range does not vary and is
25 constant even if the detection value acquired by the
acquiring section 55 varies. In the example of FIG. 12,
the normal range includes the foreign substance
determination range, and is set to be wider than the foreign
substance determination range.
30 In the example of FIG. 12 in which the foreign
substance determination range is defined so as to be a fixed
50
range, it is difficult to detect, in a distinguished manner,
the temperature drift and the entering/separation of the
foreign substances. However, when the temperature drift
does not become a problem, for example, when a sufficient
5 time has elapsed from the power activation of the clearer
15, and when the high performance LED is used as the light
projecting section 41, the entering/separation of the
foreign substances can be satisfactorily detected even if
the foreign substance determination is fixedly defined.
10 As described above, the clearer 15 of the present
embodiment includes the light projecting section 41, the
light receiving section 42, and the clearer control section
50. The light projecting section 41 projects light on the
detection region 36 through which the yarn 10 can travel.
15 The light receiving section 42 receives the light projected
from the light projecting section 41, and outputs an
electric signal corresponding to the light receiving amount.
The detection value corresponding to the light receiving
amount of the light receiving section 42 is input to the
20 clearer control section 50. The clearer control section
50 includes the yarn state evaluating section 53, the
adjusting section 54, and the foreign substance responding
processing section 59. The yarn state evaluating section
53 evaluates the state of the yarn 10 existing in the
25 detection region 36 based on the detection value. The
adjusting section 54 carries out the adjusting process of
adjusting the drive control value of the light projecting
section 41 so that the detection value becomes a
predetermined value in the state where the yarn 10 does not
30 exist in the detection region 36. The foreign substance
responding processing section 59 carries out the foreign
51
substance responding process when the detection value is
outside a predetermined foreign substance determination
range continuously for a predetermined foreign substance
determination time in the state where the yarn 10 does not
5 exist in the detection region 36. The adjusting section
54 again carries out the adjusting process when the
detection value is outside a normal range, which is a range
of the detection value set in advance so as to have a wider
range than the foreign substance determination range, in
10 the state where the yarn 10 does not exist in the detection
region.
Thus, if the detection value in the state where the
yarn 10 does not exist in the detection region 36 is outside
the foreign substance determination range continuously for
15 a predetermined foreign substance determination time,
determination is made that the entering state of the foreign
substances have changed, the predetermined foreign
substance determination process is carried out, and the
process can be appropriately performed with respect to the
20 entering/separation of the foreign substances. With the
detection value being outside the foreign substance
determination range continuously for a predetermined
foreign substance determination time as a condition, for
example, even if the detection value input to the clearer
25 control section 50 becomes unstable at the time of the
normal doffing operation, the foreign substance entering
state can be prevented from being mistakenly determined as
being changed.
In the clearer 15 of the present embodiment, the
30 adjusting section 54 may be configured to carry out the
adjusting process again when the detection value is outside
52
the normal range continuously for a predetermined
adjustment determination time in the state where the yarn
10 does not exist in the detection region 36.
In this case, for example, the wasteful adjusting
5 process can be prevented from being carried out due to the
noise appearing in the detection value.
Furthermore, the clearer 15 of the present embodiment
includes the foreign substance removing device configured
to include the first blow-out port 151, the second blow-out
10 port 152, and the compressed air electromagnetic valve 48
to remove the foreign substances existing in the detection
region 36. The foreign substance responding process
carried out by the foreign substance responding processing
section 59 includes the process of operating the foreign
15 substance removing device.
Thus, the foreign substances of the detection region
36 can be removed, and a state suitable for the adjusting
process, and the like can be obtained.
Furthermore, in the clearer 15 of the present
20 embodiment, the foreign substance removing device removes
the foreign substance by blowing air to the detection region
36.
Therefore, the foreign substances existing in the
detection region 36 can be removed with a simple
25 configuration.
Furthermore, in the clearer 15 of the present
embodiment, the foreign substance responding process
carried out by the foreign substance responding processing
section 59 includes a process of causing the adjusting
30 section 54 to carry out the adjusting process again.
When the adjusting process is carried out again, the
53
influence of the foreign substances with respect to the
detection value can be effectively eliminated.
The clearer 15 of the present embodiment includes the
yarn presence/absence determining section 56 adapted to
5 determine whether or not the yarn 10 exists in the detection
region 36. The foreign substance responding process
carried out by the foreign substance responding processing
section 59 includes a process of operating such that the
yarn 10 does not exist in the detection region 36 even if
10 the yarn presence/absence determining section 56
determines that the yarn 10 exists in the detection region
36.
In other words, when the foreign substance responding
processing section 59 determines that the foreign
15 substances have entered or separated, the clearer 15 cannot
accurately evaluate the yarn 10 due to the influence of the
foreign substances, and thus it is not appropriate to start
the winding in the yarn winding machine. Thus, in this case,
the clearer 15 operates such that the yarn 10 is not set,
20 so that the winding can be reliably prevented from being
started thereafter.
In the clearer 15 of the present embodiment, the yarn
presence/absence determining section 56 determines whether
or not the yarn 10 exists in the yarn path in the detection
25 region 36.
Thus, the clearer 15 can reliably detect whether or
not the yarn 10 exists in the yarn path. When the foreign
substance responding processing section 59 determines that
the foreign substances have entered or separated, the
30 clearer 15 can operate such that the yarn 10 does not exist
in the yarn path.
54
The foreign substance responding process carried out
by the foreign substance responding processing section 59
may include at least one of a process of outputting a foreign
substance signal, a process of outputting a winding
5 inhibiting signal of inhibiting the start of winding of the
yarn 10 by the winding section 18, and a process of
outputting the yarn joining signal for causing the yarn
joining device to carry out the yarn joining operation.
Thus, various foreign substance responding processes
10 can be carried out.
The clearer 15 of the present embodiment includes the
display lamp 46 and the display 47. The display lamp 46
and the display 47 make a notification when the detection
value is outside a foreign substance determination range
15 continuously for a foreign substance determination time in
the state where the yarn 10 does not exist in the detection
region 36.
Thus, the operator operating the yarn winding machine
(yarn winding unit 1) can recognize the entering and
20 separation of the foreign substances to and from the
detection region 36 with the display lamp 46 and the display
47. Furthermore, the operator can manually stop the
winding of the yarn winding machine in accordance with the
notification.
25 In the clearer 15 of the present embodiment, the
display 47 that notifies the operator is configured as a
display device capable of displaying at least one of
characters, symbols, and figures.
Thus, the notification can be made to the operator
30 with a simple configuration. Furthermore, the detailed
content can be notified to the operator by displaying
55
characters and the like on the screen.
Moreover, in the clearer 15 of the present embodiment,
the display lamp 46 that notifies the operator is configured
as a lamp that can be lighted.
5 Thus, the notification can be made to the operator
with a simple configuration. A status related to the
foreign substances can be notified with the lighting state
of the lamp, and thus the operator can easily check the
entering/separation of the foreign substances even from
10 remote places.
Moreover, in the clearer 15 of the present embodiment,
when a state where the detection value is outside the
foreign substance determination beyond the upper limit
value of the foreign substance determination range is
15 continued for a predetermined time (specifically, foreign
substance determination time) as illustrated in FIG. 7 in
the state where the yarn 10 does not exist in the detection
region 36, the foreign substance responding processing
section 59 determines that foreign substances have entered
20 the detection region 36. When a state where the detection
value is outside the foreign substance determination beyond
the lower limit value of the foreign substance
determination range is continued for a predetermined time
(specifically, foreign substance determination time) as
25 illustrated in FIG. 10 in the state where the yarn 10 does
not exist in the detection region 36, the foreign substance
responding processing section 59 determines that the
foreign substances have separated from the detection region
36.
30 Thus, the foreign substance responding processing
section 59 can determine, in a distinguished manner, the
56
entering and the separation of the foreign substances to
and from the detection region 36.
In the clearer 15 of the present embodiment, the
foreign substance determination range is relatively
5 defined with the reference value, which is a past detection
value, as a reference. When the detection value is greater
than or equal to the lower limit value and smaller than or
equal to the upper limit value of the foreign substance
determination range, the foreign substance responding
10 processing section 59 uses the new foreign substance
determination range defined with the relevant detection
value as the reference value in the next determination.
Thus, the foreign substance responding processing
section 59 can grasp whether or not the entering state of
15 the foreign substances to the detection region 36 is changed
with a high accuracy.
The foreign substance determination range may be
fixedly defined as illustrated in the example of FIG. 12.
In this case, the determination on the
20 entering/separation of the foreign substances can be easily
carried out.
The clearer 15 of the present embodiment includes the
yarn presence/absence determining section 56 adapted to
determine whether or not the yarn 10 exists in the detection
25 region 36. The yarn presence/absence determining section
56 determines that the yarn 10 exists in the detection
region 36 when the detection value is greater than or equal
to the predetermined yarn presence/absence determination
threshold value. The yarn presence/absence determination
30 threshold value is set to a value outside the foreign
substance determination range.
57
Thus, the clearer 15 can grasp the existence of the
yarn 10 in a manner distinguished from the foreign
substances such as fiber waste.
Preferred embodiments of the present invention have
5 been described above, but the above-described
configurations may be modified as below.
The foreign substance responding process carried out
by the foreign substance responding processing section 59
may be differed between the determination that the foreign
10 substances have entered the detection region 36 and the
determination that the foreign substances have separated
from the detection region 36. For example, the air is
injected from the first blow-out port 151 and the second
blow-out port 152 to remove the foreign substances in the
15 case of FIG. 7 in which the foreign substances enter, and
the injection of air is not carried out in the case of FIG.
10 in which the foreign substances separate.
The configuration of blowing air to the detection
region 36 is not limited to the above-described
20 configuration. For example, either the first blow-out
port 151 or the second blow-out port 152 may be omitted.
The air ejection port may not be formed in the housing 37,
an air nozzle may be formed at the distal end of appropriate
piping installed outside, and the air may be injected to
25 the recess 38 from the air nozzle.
The foreign substances can be removed without using
air, and for example, a foreign substance removing device
for cleaning by inserting a thin brush into the recess 38
formed in the housing 37 of the clearer 15 may be arranged.
30 Furthermore, the configuration for removing the
foreign substances may be omitted, and the manual removal
58
of foreign substances from the recess 38 by the operator
may be urged with the display lamp 46 and the display 47.
The display 47 may not be installed.
In the above-described embodiment, the
5 entering/separation of the foreign substances with respect
to the detection region 36 is determined using the light
receiving section 42 adapted to receive the transmitted
light, which is the light emitted from the light projecting
section 41 toward the yarn 10 and passed through the yarn
10 10. However, the entering/separation of the foreign
substances with respect to the detection region 36 may be
determined using the light receiving section adapted to
receive the reflected light, which is the light emitted from
the light projecting section 41 toward the yarn 10 and
15 reflected by the yarn 10.
In the above-described embodiment, the clearer 15
includes the cutter 16, and the yarn 10 can be cut when the
yarn defect is detected. However, the yarn monitoring
device that does not include the cutter 16 may be adopted.
20 In other words, the yarn monitoring device of the present
invention may be a device that carries out only the
monitoring of the state of the yarn.
In the above-described embodiment, the inverting
process is carried out by the amplifier 43 arranged at the
25 post-stage of the light receiving section 42. Accordingly,
the greater the light receiving amount of the light
receiving section 42, the smaller the output voltage of the
amplifier 43. However, an amplifier that does not carry
out the inverting process described above may be used. In
30 this case, the vertical axis in the graphs illustrated in
FIGS. 6 to 10 and FIG. 12 is turned upside down, so that
59
the magnitude relationship of the detection value is
inverted in the determination related to the
entering/separation of the foreign substance, the normal
range, and the presence/absence of the yarn.
5 The yarn winding machine is not limited to the
spinning machine and the automatic winder, and may be a yarn
winding machine having other configurations.
According to a first aspect of the present invention,
a yarn monitoring device having the following configuration
10 is provided. Specifically, a yarn monitoring device
includes a light projecting section, a light receiving
section, and a control section. The light projecting
section is adapted to project light on a detection region
through which a yarn can travel. The light receiving
15 section is adapted to receive the light projected from the
light projecting section. The control section receives a
detection value corresponding to a light receiving amount
of the light receiving section. The control section
includes an evaluating section, a light projection
20 adjusting section, and a foreign substance responding
processing section. The evaluating section is adapted to
evaluate a state of the yarn existing in the detection
region based on the detection value. The light projection
adjusting section is adapted to carry out a light projection
25 adjusting process of adjusting a drive control value of the
light projecting section so that the detection value
becomes a predetermined value in a state where the yarn does
not exist in the detection region. The foreign substance
responding processing section is adapted to carry out a
30 foreign substance responding process when the detection
value is outside a predetermined foreign substance
60
determination range continuously for a predetermined
foreign substance determination time in the state where the
yarn does not exist in the detection region. The light
projection adjusting section carries out the light
5 projection adjusting process again when the detection value
is outside a normal range, which is a range of a detection
value set in advance, so as to have a wider width than a
width of the foreign substance determination range in the
state where the yarn does not exist in the detection region
10 Thus, if the detection value in the state where the
yarn does not exist in the detection region is outside the
foreign substance determination range continuously for a
predetermined foreign substance determination time,
determination is made that the entering state of the foreign
15 substances has changed and the predetermined foreign
substance responding process is carried out, and hence the
entering/separation of the foreign substances can be
appropriately responded. With the detection value being
outside the foreign substance determination range
20 continuously for a predetermined foreign substance
determination time as a condition, for example, the foreign
substance entering state can be prevented from being
mistakenly determined as being changed even if the
detection value input to the control section becomes
25 unstable at the time of the normal doffing operation in the
yarn winding machine equipped with the yarn monitoring
device.
In the above-described yarn monitoring device, the
light projection adjusting section preferably carries out
30 the light projection adjusting process again when the
detection value is outside the normal range continuously
61
for a predetermined light projection adjustment
determination time in the state where the yarn does not
exist in the detection region.
In this case, for example, the wasteful light
5 projection adjusting process can be prevented from being
carried out due to the noise appearing in the detection
value.
The above-described yarn monitoring device
preferably has the following configuration. Specifically,
10 the yarn monitoring device includes a foreign substance
removing device adapted to remove foreign substances
existing in the detection region. The foreign substance
responding process carried out by the foreign substance
responding processing section includes a process of
15 operating the foreign substance removing device.
Thus, the foreign substances of the detection region
can be removed, and a state suitable for the light
projection adjusting process and the like can be obtained.
In the above-described yarn monitoring device, the
20 foreign substance removing device preferably removes the
foreign substances by blowing air to the detection region.
Therefore, the foreign substances existing in the
detection region can be removed with a simple
configuration.
25 In the above-described yarn monitoring device, the
foreign substance responding process carried out by the
foreign substance responding processing section preferably
includes causing the light projection adjusting section to
carry out the light projection adjusting process again.
30 When the light projection adjusting process is
carried out again, the influence of the foreign substances
62
with respect to the detection value can be effectively
eliminated.
The above-described yarn monitoring device
preferably has the following configuration. Specifically,
5 the yarn monitoring device further includes a yarn
presence/absence determining section adapted to determine
whether or not the yarn exists in the detection region. The
foreign substance responding process carried out by the
foreign substance responding processing section includes
10 a process of operating such that the yarn does not exist
in the detection region even when the yarn presence/absence
determining section determines that the yarn exists in the
detection region.
In other words, when the foreign substance responding
15 processing section determines that the foreign substances
have entered or separated, the yarn monitoring device
cannot accurately evaluate the yarn due to the influence
of the foreign substances, and thus it is not appropriate
to start the winding in the yarn winding machine including
20 such a yarn monitoring device. Thus, in this case, the yarn
monitoring device operates (behaves) such that the yarn is
not set, so that the winding can be reliably prevented from
being started thereafter.
In the above-described yarn monitoring device, the
25 yarn presence/absence determining section preferably
determines whether or not the yarn is located in the yarn
path in the detection region.
Thus, the yarn monitoring device can reliably detect
whether or not the yarn exists in the yarn path.
30 Furthermore, when the foreign substance responding
processing section determines that the foreign substances
63
have entered or separated, the yarn monitoring device can
operate such that the yarn does not exist in the yarn path.
In the above-described yarn monitoring device the
foreign substance responding process carried out by the
5 foreign substance responding processing section preferably
includes a process of outputting a foreign substance
detection signal.
The above-described yarn monitoring device
preferably has the following configuration. Specifically,
10 a textile machine including the yarn monitoring device
includes a winding section adapted to wind the yarn and form
a package. The foreign substance responding process
carried out by the foreign substance responding processing
section includes a process of outputting a winding
15 inhibiting signal of inhibiting the winding of the yarn by
the winding section.
The above-described yarn monitoring device
preferably has the following configuration. Specifically,
a textile machine including the yarn monitoring device
20 includes a yarn joining device adapted to carry out a yarn
joining operation. The foreign substance responding
process carried out by the foreign substance responding
processing section includes a process of outputting a yarn
joining signal for causing the yarn joining device to carry
25 out the yarn joining operation.
Thus, various foreign substance responding processes
can be carried out.
The above-described yarn monitoring device
preferably has the following configuration. Specifically,
30 the yarn monitoring device includes a notifying device.
The notifying device is adapted to make a notification when
64
the detection value is outside the foreign substance
determination range continuously for the foreign substance
determination time in the state where the yarn does not
exist in the detection region.
5 Thus, the operator can grasp the entering and
separation of the foreign substances to and from the
detection region by the notification of the notifying
device. Furthermore, the operator can manually stop the
winding of the yarn winding machine including the yarn
10 monitoring device, for example, by the notification.
In the above-described yarn monitoring device, the
notifying device is preferably a display device capable of
displaying at least one of characters, symbols, and
figures.
15 Thus, the notification can be made to the operator
with a simple configuration. The detailed content can be
notified to the operator by displaying characters and the
like on the screen.
In the yarn monitoring device, the notifying device
20 is preferably an illumination device that can be lighted.
Thus, the notification can be made to the operator
with a simple configuration. Furthermore, a status
related to the foreign substances can be notified with the
lighting state of the illumination device, so that the
25 operator can easily check the entering/separation of the
foreign substances even from remote places.
The above-described yarn monitoring device
preferably has the following configuration. Specifically,
the foreign substance responding processing section
30 determines that the foreign substances have entered the
detection region when a state where the detection value is
65
outside the foreign substance determination range beyond
a limit value on one side of the foreign substance
determination range is continued for a predetermined time
in the state where the yarn does not exist in the detection
5 region. The foreign substance responding processing
section determines that the foreign substances separated
from the detection region when a state where the detection
value is outside the foreign substance determination range
beyond a limit value on the other side of the foreign
10 substance determination range is continued for a
predetermined time in the state where the yarn does not
exist in the detection region.
Thus, the foreign substance responding processing
section can determine, in a distinguished manner, the
15 entering and the separation of the foreign substances to
and from the detection region.
The above-described yarn monitoring device
preferably has the following configuration. Specifically,
the foreign substance determination range is relatively
20 defined with a reference value, which is a past detection
value, as a reference. When the detection value is greater
than or equal to a lower limit value and smaller than or
equal to an upper limit value of the foreign substance
determination range, the foreign substance responding
25 processing section uses a new foreign substance
determination range defined with the relevant detection
value as a reference value in the next determination.
Thus, the foreign substance responding processing
section can grasp whether or not the entering state of the
30 foreign substances to the detection region changes with a
high accuracy.
66
In the yarn monitoring device, however, the foreign
substance determination range may be fixedly defined.
In this case, the determination on the
entering/separation of the foreign substances can be easily
5 carried out.
The above-described yarn monitoring device
preferably has the following configuration. Specifically,
the yarn monitoring device further includes a yarn
presence/absence determining section adapted to determine
10 whether or not the yarn exists in the detection region. The
yarn presence/absence determining section determines that
the yarn exists in the detection region when the detection
value is greater than or equal to the predetermined yarn
presence/absence determination threshold value. The yarn
15 presence/absence determination threshold value is set to
a value outside the foreign substance determination range.
Thus, the yarn monitoring device can grasp the
existence of the yarn in a manner distinguished from the
foreign substances such as fiber waste.
20 According to a second aspect of the present invention,
a yarn winding machine including the yarn monitoring
device; and a winding section adapted to wind a yarn that
passes through the yarn monitoring device to form a package
is provided.
25 Thus, the state of the yarn can be accurately
evaluated and the yarn can be wound while appropriately
responding to the entering/separation of foreign
substances in and from the detection region.
According to a third aspect of the present invention,
30 a yarn monitoring method is provided.

We claim:
1. A yarn monitoring device comprising:
a light projecting section adapted to project light
5 on a detection region through which a yarn travels;
a light receiving section adapted to receive the
light projected from the light projecting section; and
a control section to which a detection value
corresponding to a light receiving amount of the light
10 receiving section is input, characterized in that
the control section includes
an evaluating section adapted to evaluate a
state of the yarn existing in the detection region based
on the detection value,
15 a light projection adjusting section adapted
to carry out a light projection adjusting process of
adjusting a drive control value of the light projecting
section so that the detection value becomes a predetermined
value in a state where the yarn does not exist in the
20 detection region, and
a foreign substance responding processing
section adapted to carry out a foreign substance responding
process when the detection value is outside a predetermined
foreign substance determination range continuously for a
25 predetermined foreign substance determination time in the
state where the yarn does not exist in the detection region,
and
the light projection adjusting section carries out
the light projection adjusting process again when a
30 detection value is outside a normal range which is a range
of the detection value set in advance so as to have a wider
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width than a width of the foreign substance determination
range in the state where the yarn does not exist in the
detection region.
5 2. The yarn monitoring device according to claim 1,
characterized in that
the light projection adjusting section carries out
the light projection adjusting process again when the
detection value is outside the normal range continuously
10 for a predetermined light projection adjustment
determination time in the state where the yarn does not
exist in the detection region.
3. The yarn monitoring device according to claim 1
15 or 2, characterized by further comprising
a foreign substance removing device adapted to remove
foreign substances existing in the detection region,
wherein
the foreign substance responding process carried out
20 by the foreign substance responding processing section
includes a process of operating the foreign substance
removing device.
4. The yarn monitoring device according to claim 3,
25 characterized in that
the foreign substance removing device removes the
foreign substances by blowing air to the detection region.
5. The yarn monitoring device according to any one
30 of claims 1 to 4, characterized in that
the foreign substance responding process carried out
69
by the foreign substance responding processing section
includes causing the light projection adjusting section to
carry out the light projection adjusting process again.
5 6. The yarn monitoring device according to any one
of claims 1 to 5, characterized by further comprising
a yarn presence/absence determining section adapted
to determine whether or not the yarn exists in the detection
region, wherein
10 the foreign substance responding process carried out
by the foreign substance responding processing section
includes a process of operating such as if the yarn does
not exist in the detection region even when the yarn
presence/absence determining section determines that the
15 yarn exists in the detection region.
7. The yarn monitoring device according to any one
of claims 1 to 5, characterized in that
the foreign substance responding process carried out
20 by the foreign substance responding processing section
includes a process of outputting a foreign substance
detection signal.
8. The yarn monitoring device according to any one
25 of claims 1 to 7, characterized in that
a textile machine including the yarn monitoring
device includes a winding section adapted to wind the yarn
to form a package, and
the foreign substance responding process carried out
30 by the foreign substance responding processing section
includes a process of outputting a winding inhibiting
70
signal of inhibiting the winding of the yarn by the winding
section.
9. The yarn monitoring device according to any one
5 of claims 1 to 8, characterized in that
a textile machine including the yarn monitoring
device includes a yarn joining device adapted to carry out
a yarn joining operation, and
the foreign substance responding process carried out
10 by the foreign substance responding processing section
includes a process of outputting a yarn joining signal for
causing the yarn joining device to carry out the yarn
joining operation.
15 10. The yarn monitoring device according to any one
of claims 1 to 9, characterized by further comprising a
notifying device, wherein
the notifying device is adapted to make a
notification when the detection value is outside the
20 foreign substance determination range continuously for the
foreign substance determination time in the state where the
yarn does not exist in the detection region.
11. The yarn monitoring device according to any one
25 of claims 1 to 10, characterized in that
the foreign substance responding processing section
determines that foreign substances enter the
detection region when a state in which the detection value
is outside the foreign substance determination range beyond
30 a limit value on one side of the foreign substance
determination range is continued for a predetermined time
71
in the state where the yarn does not exist in the detection
region, and
determines that foreign substances separated from
the detection region when a state in which the detection
5 value is outside the foreign substance determination range
beyond a limit value on the other side of the foreign
substance determination range is continued for a
predetermined time in the state where the yarn does not
exist in the detection region.
10
12. The yarn monitoring device according to claim
11, characterized in that
the foreign substance determination range is
relatively defined with a reference value, which is a past
15 detection value, as a reference, and
when the detection value is greater than or equal to
a lower limit value and smaller than or equal to an upper
limit value of the foreign substance determination range,
the foreign substance responding processing section uses
20 a new foreign substance determination range defined with
the detection value as a reference value in the next
determination.
13. The yarn monitoring device according to claim
25 11, characterized in that
the foreign substance determination range is fixedly
defined.
14. The yarn monitoring device according to any one
30 of claims 1 to 13, characterized by further comprising
a yarn presence/absence determining section adapted
72
to determine whether or not the yarn exists in the detection
region, wherein
the yarn presence/absence determining section
determines that the yarn exists in the detection region when
5 the detection value is greater than or equal to a
predetermined yarn presence/absence determination
threshold value, and
the yarn presence/absence determination threshold
value is set to a value outside the foreign substance
10 determination range.
15. A yarn winding machine characterized by
comprising:
the yarn monitoring device according to any one of
15 claims 1 to 14; and
a winding section adapted to wind a yarn that passes
through the yarn monitoring device to form a package.
16. A method for yarn monitoring comprising the
20 following steps:
projecting light on a detection region through which
a yarn travels;
receiving the light projected from a light projecting
section; and
25 detecting a detection value corresponding to a light
receiving amount,
evaluating a state of the yarn existing in the
detection region based on the detection value,
carrying out a light projection adjusting process of
30 adjusting a drive control value of the light projecting
section so that the detection value becomes a predetermined
73
value in a state where the yarn does not exist in the
detection region, and
carrying out a foreign substance responding process
when the detection value is outside a predetermined foreign
5 substance determination range continuously for a
predetermined foreign substance determination time in the
state where the yarn does not exist in the detection region,
and
carrying out the light projection adjusting process
10 again when a detection value is outside a normal range which
is a range of the detection value set in advance so as to
have a wider width than a width of the foreign substance
determination range in the state where the yarn does not
exist in the detection region.