TECHNICAL FIELD
[0001] The present disclosure relates to a spinning machine.
BACKGROUND
[0002] The spinning machine described in Japanese Unexamined Patent Publication No.
2013-049932 is known as a conventional spinning machine. The spinning machine described in Japanese
Unexamined Patent Publication No.
2013-049932 includes a spinning device generating yarn, a winding device winding yarn generated
by the spinning device into a package, and a detecting unit detecting the tension
of traveling yarn between the spinning device and the winding device.
SUMMARY
[0003] Tension of traveling yarn is one of factors affecting the quality of yarn, and appropriate
control on the tension of yarn wound into a package by the winding device can thus
improve the quality of the yarn.
[0004] An embodiment of the present disclosure aims to provide a spinning machine enabling
improvement of the quality of yarn.
[0005] A spinning machine according to an embodiment of the present disclosure includes
a yarn forming unit configured to form yarn from a spun material, a winding device
configured to wind yarn formed by the yarn forming unit, a tension detecting unit
configured to detect the tension of yarn in an upstream side from the winding device
in a direction in which the yarn travels, and a control unit configured to control
the yarn forming unit based on a result of detection by the tension detecting unit
such that the yarn is wound onto the winding device with adjustment of the tension
added to the spun material in the yarn forming unit. The control unit adjusts the
tension by controlling a device of the yarn forming unit disposed at least in an upstream
side or in a downstream side from a position at which the spun material is twisted
in the direction in which the yarn travel.
[0006] A spinning machine according to an embodiment of the present disclosure can maintain
the tension of yarn within a predetermined range by providing feedback control to
devices based on the tension of yarn detected by the tension detecting unit. With
this configuration, the spinning machine can improve the quality of yarn.
[0007] In an embodiment, the yarn forming unit may include a drafting device configured
to draft a fiber bundle used as a spun material. The drafting device may include a
plurality of pairs of rollers including a pair of front rollers disposed in a most
downstream position in a direction in which the fiber bundle is drafted. The control
unit may control the circumferential speed of the pair of front rollers based on the
result of detection by the tension detecting unit. The feed ratio of the fiber bundle
changes with a change in the circumferential speed of the pair of front rollers of
the drafting device. The change in the feed ratio can change the tension of the fiber
bundle (the yarn) in the downstream side from the pair of front rollers. Consequently,
in the spinning machine, effective control on the tension of yarn can be achieved
by controlling the circumferential speed of the pair of front rollers based on a result
of detection by the tension detecting unit.
[0008] In an embodiment, when the tension of yarn is detected below a predetermined range
in a result of detection, the control unit may provide control of decreasing the current
circumferential speed of the pair of front rollers until the tension of the yarn increases
to the predetermined range. On the contrary, when the tension of the yarn is detected
beyond the predetermined range in a result of detection, the control unit may provide
control of increasing the current circumferential speed of the pair of front rollers
until the tension of the yarn decreases to the predetermined range. An increase in
the circumferential speed can decrease the tension of yarn, whereas a decrease in
the circumferential speed of the pair of front rollers can increase the tension of
yarn. The control unit controls the circumferential speed of the pair of front rollers
based on a result of detection so as to maintain the tension of the yarn within a
predetermined range.
[0009] In an embodiment, the yarn forming unit includes a yarn storage roller disposed upstream
of the winding device in a direction in which the yarn travels and configured to store
the yarn. The control unit may control the number of rotations per unit time of the
yarn storage roller based on a result of detection by the tension detecting unit such
that the tension of the yarn detected by the tension detecting unit falls within a
predetermined range. A change in the number of rotations per unit time of the yarn
storage roller changes the feed ratio of the yarn. The change in the feed ratio can
change the tension of the yarn stored in the yarn storage roller. In the spinning
machine, the tension of yarn is effectively controlled by controlling the number of
rotations of the yarn storage roller based on a result of detection by the tension
detecting unit.
[0010] In an embodiment, when the tension of yarn is detected below a predetermined range
in the result of detection, the control unit may provide control of increasing the
current number of rotations of the yarn storage roller until the tension of the yarn
increases to the predetermined range. On the contrary, when the tension of yarn is
detected beyond the predetermined range in a result of detection, the control unit
may provide control of decreasing the current number of rotations of the yarn storage
roller until the tension of the yarn decreases to the predetermined range. An increase
in the number of rotations of the yarn storage roller can increase the tension of
yarn, whereas a decrease in the number of rotations of the yarn storage roller can
decrease the tension of yarn. The control unit controls the number of rotations of
the yarn storage roller based on a result of detection so as to maintain the tension
of yarn within a predetermined range.
[0011] In an embodiment, the spinning machine may include an air spinning device configured
to generate the yarn by applying swirling airflow to a fiber bundle, and the yarn
storage roller may store the yarn while drawing the yarn generated by the air spinning
device. With this configuration, the yarn storage roller can control the tension of
yarn generated by the air spinning device, and consequently, yarn is generated in
the air spinning device at optimum tension, which can improve the quality of the yarn.
[0012] A spinning machine according to an embodiment of the present disclosure includes
a yarn forming unit including a core yarn supply device that includes a supporting
unit configured to support a core yarn package with core yarn wound thereon and a
tension adding unit configured to add tension to the core yarn unwound from the core
yarn package, the yarn forming unit being configured to form yarn from a spun material
including the core yarn, a winding device configured to wind the yarn formed by the
yarn forming unit, a tension detecting unit configured to detect tension of the yarn
in the upstream side from the winding device in a direction in which the yarn travels,
and a control unit configured to control the tension adding unit based on a result
of detection by the tension detecting unit such that the yarn is wound onto the winding
device with adjustment of tension added to the spun material in the yarn forming unit.
[0013] The spinning machine according to an embodiment of the present disclosure can maintain
the tension of yarn within a predetermined range by providing feedback control to
devices based on the tension of yarn detected by the tension detecting unit. The spinning
machine in this configuration can improve the quality of yarn including core yarn.
[0014] In an embodiment, the control unit may control the tension adding unit based on a
result of detection by the tension detecting unit such that the tension of the yarn
detected by the tension detecting unit falls within a predetermined range. This process
can improve the quality of yarn wound by the winding device.
[0015] According to an embodiment of the present disclosure, the quality of yarn can be
improved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016]
FIG. 1 is a front view of a spinning machine according to an embodiment.
FIG. 2 is a side view of a spinning unit of the spinning machine of FIG. 1.
FIG. 3 is a block diagram illustrating the configuration of a part of the spinning
unit.
FIG. 4 is a perspective view of a core yarn supply device in the spinning unit illustrated
in FIG. 2.
FIG. 5A is a side view of a tension adding mechanism in the core yarn supply device
illustrated in FIG. 4.
FIG. 5B is another side view of the tension adding mechanism in the core yarn supply
device illustrated in FIG. 4.
FIG. 6 is a block diagram illustrating the configuration of a part of a spinning unit
of a spinning machine according to another embodiment.
DETAILED DESCRIPTION
[0017] An embodiment will now be described with reference to the drawings. In the drawings,
like numerals indicate like components, and overlapping description will be omitted.
[0018] As illustrated in FIG. 1, a spinning machine 1 includes a plurality of spinning units
2, a splicing carrier 3, a doffing carrier (not illustrated), a first end frame 4,
and a second end frame 5. The spinning units 2 are aligned in a row. Each spinning
unit 2 generates yarn Y and winds the yarn into a package P. When the yarn Y is cut
or breaks in a spinning unit 2 for any reason, the splicing carrier 3 splices the
yarn Y in the spinning unit 2. When the package P becomes a full roll, completes in
a spinning unit 2, the doffing carrier doffs the package P and supplies a new bobbin
B to the spinning unit 2.
[0019] The first end frame 4 accommodates therein a collection device and the like for collecting
fiber waste, yarn waste, and others generated in the spinning unit 2. The second end
frame 5 accommodates therein an air supply unit adjusting air pressure of compressed
air (air) supplied to the spinning machine 1 and supplying air to the units in the
spinning machine 1, a driving motor for supplying power to the units in the spinning
unit 2, and others. The second end frame 5 includes a machine control device 100,
a display screen 102, and an input key 104. The machine control device 100 intensively
manages and controls the units of the spinning machine 1. The display screen 102 can
display, for example, information on the settings and/or the status of the spinning
unit 2. An operator performs necessary operations through the input key 104, thereby
setting the spinning unit 2.
[0020] As FIGs. 1 and 2 illustrate, each spinning unit 2 includes, in the order from the
upstream side in the direction in which the yarn Y travels, a drafting device 6, a
core yarn supply device 7, an air spinning device 8, a yarn monitoring device 9, a
tension sensor (a tension detecting unit) 10, a yarn storage device 11, a waxing device
12, and a winding device 13. In the embodiment, the drafting device 6, the core yarn
supply device 7, and a yarn storage roller 11a (described later) of the yarn storage
device 11 constitute a yarn forming unit forming the yarn Y from a spun material while
adjusting the tension of the spun material. The drafting device 6, the core yarn supply
device 7, and the yarn storage roller 11a of the yarn storage device 11 are disposed
in at least one of the upstream side and the downstream side from a position (the
air spinning device 8) at which the spun yarn is twisted. A unit controller (the control
unit) 15 is provided in every certain number of spinning units 2 and controls operations
of the spinning units 2. The drafting device 6, the core yarn supply device 7, and
the yarn storage device 11 in the spinning unit 2 are devices affecting the tension
of the yarn Y.
[0021] The drafting device 6 drafts a sliver (a fiber bundle, a spun material) S. The drafting
device 6 includes, in the order from the upstream side in the direction in which the
sliver S travels, a pair of back rollers 16, a pair of third rollers 17, a pair of
middle rollers 18, and a pair of front rollers 19. The pair of front rollers 19 are
disposed in the most downstream position in a direction of drafting. Each pair of
rollers 16, 17, 18, and 19 includes a bottom roller and a top roller. The bottom roller
is driven and rotated by a driving motor installed in the second end frame 5. The
top roller of the pair of middle rollers 18 includes an apron belt 18a. The bottom
roller of the pair of middle rollers 18 includes an apron belt 18b.
[0022] The core yarn supply device 7 unwinds core yarn (a spun material) C from a core yarn
package CP and supplies the core yarn C to the drafting device 6. Specifically, the
core yarn supply device 7 supplies the core yarn C onto the traveling path of the
fiber bundle F from between the pair of middle rollers 18 and the pair of front rollers
19, whereby the core yarn C is supplied to the air spinning device 8 together with
the fiber bundle F.
[0023] The air spinning device 8 generates the yarn Y by twisting the fiber bundle F drafted
by the drafting device 6 using swirling airflow. More specifically (although not illustrated
in the drawings), the air spinning device 8 includes a spinning room, a fiber guiding
unit, a swirling airflow generating nozzle, and a hollow guide shaft. The fiber guiding
unit guides the fiber bundle F supplied from the drafting device 6 disposed in the
upstream side to the spinning room. The swirling airflow generating nozzle is disposed
around a path on which the fiber bundle F travels. Swirling airflow is generated in
the spinning room with the swirling airflow generating nozzle spraying air. The swirling
airflow reverses and swirls the fiber tips of a plurality of fibers included in the
fiber bundle F. The hollow guide shaft guides the yarn Y from the spinning room to
the outside of the air spinning device 8.
[0024] The yarn monitoring device 9 is disposed between the air spinning device 8 and the
yarn storage device 11 and monitors information on traveling yarn Y. Specifically,
the yarn monitoring device 9 detects whether the yarn Y has any defects based on the
monitored information. Upon detection of a defect on the yarn, the yarn monitoring
device 9 transmits a yarn defect detection signal to the unit controller 15. The yarn
monitoring device 9 detects abnormality in the diameter of the yarn Y, a foreign matter
contained in the yarn Y, and/or the like as a defect of the yarn Y. The yarn monitoring
device 9 further detects yarn breakage and others.
[0025] The tension sensor 10 disposed between the air spinning device 8 and the yarn storage
device 11 measures the tension of traveling yarn Y and transmits a tension measuring
signal (a result of detection) to the unit controller 15. When the unit controller
15 determines that abnormality has occurred based on at least one of a result of detection
by the yarn monitoring device 9 and a result of detection by the tension sensor 10,
the yarn Y is cut in the spinning unit 2. Specifically, air supply to the air spinning
device 8 stops, generation of the yarn Y is terminated, and the yarn Y is accordingly
cut. In another way, the yarn Y may be cut with a cutter separately provided.
[0026] The waxing device 12 disposed between the yarn storage device 11 and the winding
device 13 applies wax to the yarn Y.
[0027] The yarn storage device 11 disposed between the air spinning device 8 and the winding
device 13 eliminates slack from the yarn Y. The yarn storage device 11 has functions
of stably drawing the yarn Y from the air spinning device 8, preventing the yarn Y
from slacking by retaining the yarn Y delivered from the air spinning device 8, for
example, in the yarn splicing operation of the splicing carrier 3, and preventing
fluctuations in the tension of the yarn Y situated downstream of the yarn storage
device 11 from spreading to the air spinning device 8.
[0028] The yarn storage device 11 includes the yarn storage roller 11a, a yarn threading
member 11b, and a motor 11c. The yarn storage roller 11a stores the yarn Y with the
yarn Y wound onto the outer peripheral surface of the yarn storage roller 11a. The
yarn threading member 11b is disposed at the downstream end of the yarn storage roller
11a. Upon a start of storage of the yarn Y, the yarn threading member 11b hooks the
yarn Y and winds the yarn onto the yarn storage roller 11a. During winding into the
package P, the yarn threading member 11b adds tension to the yarn Y unwound from the
yarn storage roller 11a. The motor 11c rotates the yarn storage roller 11a. As illustrated
in FIG. 3, a motor driver 11d controls driving of the motor 11c. Specifically, the
motor driver 11d controls driving of the motor 11c based on a signal output from the
unit controller 15.
[0029] The winding device 13 winds the yarn Y onto the bobbin B and forms the package P.
The winding device 13 includes a cradle arm 21, a winding drum 22, and a traverse
guide 23. The cradle arm 21 rotatably supports the bobbin B. The cradle arm 21 is
swingably supported by a supporting shaft 24 and has the surface of the bobbin B or
the surface of the package P contact with the surface of the winding drum 22 at appropriate
pressure. The driving motor (not illustrated) installed in the second end frame 5
simultaneously drives the winding drums 22 of a plurality of spinning units 2. With
this drive, the bobbin B or the package P of each spinning unit 2 is rotated in a
direction of winding. The traverse guide 23 of each spinning unit 2 is mounted on
a shaft 25 shared by a plurality of spinning units 2. With the driving motor in the
second end frame 5 driving the shaft 25 in a direction of the rotational axis of the
winding drum 22 in a reciprocating manner, the traverse guide 23 has the yarn Y traverse
a rotating bobbin B or package P at a certain width.
[0030] When the yarn Y is cut or breaks in a spinning unit 2 for any reason, the splicing
carrier 3 runs to the spinning unit 2 and performs a splicing operation. The splicing
carrier 3 includes a splicing device 26, a suction pipe 27, and a suction mouth 28.
The suction pipe 27 is rotatably supported by a support shaft 31. The suction pipe
27 catches the yarn Y sent from the air spinning device 8 and guides the yarn Y to
the splicing device 26. The suction mouth 28 is rotatably supported by a support shaft
32. The suction mouth 28 catches the yarn Y sent from the winding device 13 and guides
the yarn Y to the splicing device 26. The splicing device 26 splices the guided pieces
of the yarn Y with each other. Examples of the splicing device 26 include a splicer
using compressed air and a knotter mechanically splicing the yarn Y.
[0031] In the splicing operation, the splicing carrier 3 rotates (reversely rotates) the
package P in a reverse direction of winding. Specifically, the cradle arm 21 is moved
by an air cylinder (not illustrated) so that the package P is separated from the winding
drum 22, and a reverse rotating roller (not illustrated) installed to the splicing
carrier 3 reversely rotates the package P.
[0032] The core yarn supply device 7 will now be described in detail. As illustrated in
FIG. 2, the core yarn supply device 7 includes a package supporting unit (a supporting
unit) 50, a core yarn supply unit 51, and a core yarn guiding unit 52.
[0033] The package supporting unit 50 supports the core yarn package CP with the center
line of the core yarn package CP horizontally extending in the front-to-back direction.
The core yarn package CP is formed with the core yarn C wound onto a core yarn bobbin
CB. The core yarn C in this embodiment is, for example, multifilament yarn. The multifilament
yarn is yarn formed by bundling a plurality of pieces of filament single yarn. The
core yarn C is unwound from the core yarn package CP and is supplied to the core yarn
supply unit 51 via a guide roller 53 guiding the core yarn C. The core yarn C may
be another kind of yarn such as monofilament yarn and spun yarn.
[0034] The core yarn supply unit 51 has functions of adding tension to supplied core yarn
C, adding slack to the core yarn C, and delivering the core yarn C (an end of the
core yarn C). The core yarn guiding unit 52 is a cylindrical member guiding the core
yarn C to the drafting device 6.
[0035] As illustrated in FIG. 4, the core yarn supply unit 51 includes a unit base 60, a
tension adding mechanism 70, a slack adding mechanism 80, a core yarn monitoring device
82, and a core yarn delivery mechanism 84. In the following description, in the traveling
path of the core yarn C in the core yarn supply unit 51, the core yarn package CP
side is referred to as an upstream side, whereas the core yarn guiding unit 52 side
is referred to as a downstream side.
[0036] The unit base 60 supports, in the order from the upstream side in a direction in
which the core yarn C is supplied, the tension adding mechanism 70, the slack adding
mechanism 80, the core yarn monitoring device 82, and the core yarn delivery mechanism
84. A core yarn guide 61 guiding the core yarn C is disposed in the most upstream
position on the unit base 60.
[0037] The tension adding mechanism 70 adds tension to the core yarn C in the downstream
side from the core yarn guide 61. As illustrated in FIGs. 5A and 5B, the tension adding
mechanism 70 includes a tension adding unit 71 and a retaining unit 72.
[0038] The tension adding unit 71 includes a fixed piece 73 and a movable piece 74. With
the core yarn C alternately hooked to the fixed piece 73 and the movable piece 74,
the core yarn C is bent a plurality of times in the tension adding unit 71. The number
of bends of the core yarn C is, for example, 20 times or less (preferably, between
twice and ten times, inclusively).
[0039] The fixed piece 73 is fixed to the unit base 60. The movable piece 74 is supported
by a support shaft (not illustrated) provided to the fixed piece 73 and openable and
closable (rotatable) with respect to the fixed piece 73. The movable piece 74 is pressed
toward a direction opening with respect to the fixed piece 73 by a spring (not illustrated)
provided to the fixed piece 73.
[0040] A plurality of shafts 73a are provided to the fixed piece 73 at certain intervals
in a direction in which the core yarn C is supplied. A plurality of projections 74a
projecting toward the fixed piece 73 are provided to the movable piece 74. When the
movable piece 74 closes with respect to the fixed piece 73 (the state in FIG. 5B),
the projections 74a are alternately positioned between the shafts 73a in the direction
in which the core yarn C is supplied. Each projection 74a has a hole 74b through which
the core yarn C passes at its leading end. The core yarn C is alternately hooked to
the shafts 73a and the holes 74b.
[0041] As illustrated in FIG. 5A, the core yarn C is bent a plurality of times when the
movable piece 74 opens with respect to the fixed piece 73. In this process, tension
is added to the core yarn C. Specifically, higher tension is added to the core yarn
C with the movable piece 74 opening with respect to the fixed piece 73 at a larger
angle, and the state of the tension adding unit 71 under this condition is referred
to as a tension added state. As illustrated in FIG. 5B, the core yarn C is substantially
linear when the movable piece 74 closes with respect to the fixed piece 73. In this
process, no tension is added to the core yarn C (or lower tension than the tension
in the tension added state is added to the core yarn C). The state of the tension
adding unit 71 under this condition is referred to as a no-tension added state.
[0042] The retaining unit 72 opens and closes the movable piece 74 with respect to the fixed
piece 73. As illustrated in FIGs. 5A and 5B, the retaining unit 72 includes a retaining
member 75 and an actuator 76. As illustrated in FIG. 3, the unit controller 15 controls
driving of the actuator 76.
[0043] The actuator 76 has the retaining member 75 abut with or separated from the movable
piece 74. More specifically, the retaining member 75 has a front end 75a abutting
with the movable piece 74 from the opposite side of the fixed piece 73, and the position
of the front end 75a is moved by the actuator 76.
[0044] When the front end 75a moves down, the movable piece 74 is pushed by the front end
75a and closes with respect to the fixed piece 73. This process turns the tension
adding unit 71 to the no-tension added state. When the front end 75a moves up, the
movable piece 74 opens with respect to the fixed piece 73 with the pressing force
of the spring. This process turns the tension adding unit 71 to the tension added
state.
[0045] The slack adding mechanism 80 adds slack to the core yarn C in the downstream side
from the tension adding mechanism 70. More specifically, the position of a front-end
guiding unit of the slack adding mechanism 80 moves from a position including the
traveling path (the continuous line in FIG. 4) of the core yarn C to another position
(the position indicated by the double chain line in FIG. 4) away from the traveling
path of the core yarn C before the core yarn delivery mechanism 84 starts delivering
the core yarn C. This process adds slack to the core yarn C. The core yarn monitoring
device 82 detects the presence of the core yarn C between the core yarn guide 61 and
the core yarn delivery mechanism 84. In FIG. 4, the core yarn monitoring device 82
is disposed downstream of the slack adding mechanism 80 in the direction in which
the core yarn C is supplied. The core yarn monitoring device 82 may be disposed upstream
of the tension adding mechanism 70. The core yarn delivery mechanism 84 is disposed
downstream of the core yarn monitoring device 82 and delivers the core yarn C (an
end of the core yarn C) to the drafting device 6 when the spinning operation starts.
[0046] A method of controlling the tension of the yarn Y with the yarn storage device 11
will now be described.
[0047] When the spinning unit 2 of the spinning machine 1 starts the spinning operation,
the tension sensor 10 measures the tension of traveling yarn Y and transmits a tension
measuring signal to the unit controller 15. The unit controller 15 rotates the yarn
storage roller 11a at the number of initial rotations set for each lot. The number
of initial rotations is preset such that the tension of the yarn Y detected by the
tension sensor 10 falls within a predetermined range. The "predetermined range" may
be a range having a certain width or may be a value without a range.
[0048] The unit controller 15 receives the tension measuring signal and determines whether
the tension of the yarn Y indicated by the tension measuring signal falls within a
predetermined range. The range for the tension of the yarn Y is input, for example,
through the input key 104 of the machine control device 100 and set. The range for
the tension of the yarn Y may be automatically set based on a set lot.
[0049] If the unit controller 15 determines that the tension of the yarn Y is out of the
predetermined range, the unit controller 15 controls the number of rotations per unit
time (hereinafter simply referred to as "the number of rotations") of the yarn storage
roller 11a. In this embodiment, the unit controller 15 controls the tension of the
yarn Y by changing the number of rotations of the yarn storage roller 11a without
changing the drafting speed (for example, the circumferential speed of the pair of
front rollers 19) of the drafting device 6. The drafting operation by the drafting
device 6, the spinning operation by the air spinning device 8, and the winding operation
by the winding device 13 are continuing in parallel with the control.
[0050] Specifically, if the tension of the yarn Y is below the predetermined range, the
unit controller 15 increases the number of rotations (rpm) of the yarn storage roller
11a from the number of initial rotations. More specifically, the unit controller 15
outputs a signal to the motor driver 11d and increases the number of rotations of
the motor 11c. This process changes the feed ratio (the difference in the delivery
speed of the yarn Y between the yarn storage roller 11a and the pair of front rollers
19) of the yarn Y determined based on the number of rotations of the yarn storage
roller 11a and the circumferential speed of the pair of front rollers 19. Specifically,
the delivery speed of the yarn Y drawn from the air spinning device 8 by the yarn
storage roller 11a becomes higher than the delivery speed of the yarn Y delivered
from the pair of front rollers 19 to the air spinning device 8. The tension of the
yarn Y increases with the change in the feed ratio. When the unit controller 15 determines
that the tension of the yarn Y has increased to the predetermined range based on the
tension measuring signal, the unit controller 15 completes the control of increasing
the number of rotations of the yarn storage roller 11a and controls the number of
rotations of the yarn storage roller 11a so that the tension of the yarn Y is maintained
within the predetermined range.
[0051] On the contrary, if the tension of the yarn Y is beyond the predetermined range,
the unit controller 15 decreases the number of rotations of the yarn storage roller
11a from the number of initial rotations. With this operation, the delivery speed
of the yarn Y drawn from the air spinning device 8 by the yarn storage roller 11a
becomes lower than the delivery speed of the yarn Y delivered from the pair of front
rollers 19 to the air spinning device 8, which accordingly changes the feed ratio
of the yarn Y. The tension of the yarn Y decreases with the change in the feed ratio.
When the unit controller 15 determines that the tension of the yarn Y has decreased
to the predetermined range based on the tension measuring signal, the unit controller
15 completes the control of decreasing the number of rotations of the yarn storage
roller 11a and controls the number of rotations of the yarn storage roller 11a so
that the tension of the yarn Y is maintained within the predetermined range.
[0052] If the unit controller 15 determines that the tension of the yarn Y is out of the
predetermined range and further determines that the tension of the yarn Y is at a
value causing abnormality on the yarn Y (for example, the tension at the value is
low enough to form a weak portion on the yarn Y), the unit controller 15 terminates
the spinning operation instead of controlling the number of rotations of the yarn
storage roller 11a.
[0053] A method of controlling the tension of the yarn Y with the core yarn supply device
7 will now be described.
[0054] When the spinning unit 2 of the spinning machine 1 starts the spinning operation,
the tension sensor 10 measures the tension of traveling yarn Y and transmits a tension
measuring signal to the unit controller 15. The unit controller 15 controls the actuator
76 such that the initial tension is added to the core yarn C by the tension adding
mechanism 70. The initial tension is preset such that the tension of the yarn Y detected
by the tension sensor 10 falls within a predetermined range. The unit controller 15
controls the actuator 76 so as to have the front end 75a positioned at the initial
position. With this process, the initial tension is added to the core yarn C.
[0055] The unit controller 15 receives the tension measuring signal and determines whether
the tension of the yarn Y indicated by the tension measuring signal falls within a
predetermined range. If the unit controller 15 determines that the tension of the
yarn Y is out of the predetermined range, the unit controller 15 controls the tension
added to the core yarn C by the tension adding mechanism 70. Specifically, if the
tension of the yarn Y is below the predetermined range, the unit controller 15 controls
the actuator 76 such that the front end 75a moves above the initial position and that
the movable piece 74 opens with respect to the fixed piece 73. The tension added to
the core yarn C increases with the move of the front end 75a. When the unit controller
15 determines that the tension of the yarn Y has increased to the predetermined range
based on the tension measuring signal, the unit controller 15 completes the control
of increasing the tension added by the tension adding mechanism 70 and controls the
tension adding mechanism 70 such that the tension of the yarn Y is maintained within
the predetermined range.
[0056] If the tension of the yarn Y is beyond the predetermined range, the unit controller
15 controls the actuator 76 such that the front end 75a moves below the initial position
and that the movable piece 74 closes with respect to the fixed piece 73. The tension
added to the core yarn C decreases with the move of the front end 75a. When the unit
controller 15 determines that the tension of the yarn Y has decreased to the predetermined
range based on the tension measuring signal, the unit controller 15 completes the
control of decreasing the tension added by the tension adding mechanism 70 and controls
the tension adding mechanism 70 such that the tension of the yarn Y is maintained
within the predetermined range.
[0057] If the unit controller 15 determines that the tension of the yarn Y is out of the
predetermined range and further determines that the tension of the yarn Y is at a
value causing abnormality on the yarn Y, the unit controller 15 terminates the spinning
operation instead of controlling the tension adding mechanism 70.
[0058] The tension of the yarn Y may be controlled by controlling at least one of the yarn
storage device 11 and the core yarn supply device 7. In other words, the tension of
the yarn Y may be controlled by controlling the number of rotations of the yarn storage
roller 11a or may be controlled by controlling the tension added to the core yarn
C by the tension adding mechanism 70. In another way, the tension of the yarn Y may
be controlled by controlling both the yarn storage roller 11a and the tension adding
mechanism 70 of the core yarn supply device 7. In any of these cases, the drafting
operation by the drafting device 6, the spinning operation by the air spinning device
8, and the winding operation by the winding device 13 are continuing in parallel with
the control.
[0059] As described above, in the spinning machine 1 according to the embodiment, devices
affecting the tension of the yarn Y are controlled based on a result of detection
by the tension sensor 10 such that the tension of the yarn Y falls within a predetermined
range. The spinning machine 1 can maintain the tension of the yarn Y within a predetermined
range by providing feedback control to the devices based on the tension of the yarn
Y detected by the tension sensor 10. The spinning machine 1 in this configuration
can thus improve the quality of the yarn Y.
[0060] In this embodiment, the unit controller 15 controls the number of rotations of the
yarn storage roller 11a based on the tension measuring signal transmitted from the
tension sensor 10 such that the tension of the yarn Y detected by the tension sensor
10 falls within a predetermined range. A change in the number of rotations per unit
time of the yarn storage roller 11a changes the feed ratio. The change in the feed
ratio accordingly changes the tension of the yarn Y stored in the yarn storage roller
11a. Consequently, in the spinning machine 1, the tension of the yarn Y is effectively
controlled by controlling the number of rotations of the yarn storage roller 11a based
on the tension measuring signal transmitted from the tension sensor 10.
[0061] Specifically, if the tension of the yarn Y is detected below a predetermined range
in the tension measuring signal, the unit controller 15 increases the number of rotations
per unit time of the yarn storage roller 11a until the tension of the yarn Y increases
to the predetermined range. On the contrary, if the tension of the yarn Y is detected
beyond the predetermined range in the tension measuring signal, the unit controller
15 decreases the number of rotations per unit time of the yarn storage roller 11a
until the tension of the yarn Y decreases to the predetermined range. An increase
in the number of rotations of the yarn storage roller 11a can increase the tension
of the yarn Y, whereas a decrease in the number of rotations of the yarn storage roller
11a can decrease the tension of the yarn Y. Consequently, the unit controller 15 controls
the number of rotations of the yarn storage roller 11a based on the tension measuring
signal, thereby maintaining the tension of the yarn Y within the predetermined range.
[0062] In this embodiment, the yarn storage roller 11a stores the yarn Y while drawing the
yarn Y generated by the air spinning device 8, which means that no delivery rollers
or nip rollers for drawing the yarn Y from the air spinning device 8 are disposed
between the air spinning device 8 and the yarn storage roller 11a. This configuration
enables control of the tension of the yarn Y generated by the air spinning device
8 using the yarn storage roller 11a. Consequently, the yarn Y is generated by the
air spinning device 8 at optimum spinning tension, which can improve the quality of
the yarn.
[0063] With the configuration that the yarn Y is drawn from the air spinning device 8 by
the delivery roller and the nip roller, the yarn Y may slip on the delivery roller.
Slip of the yarn Y may result in instable control on the tension of the yarn Y. In
this embodiment, the yarn Y is drawn from the air spinning device 8 by the yarn storage
roller 11a. The yarn storage roller 11a draws the yarn Y from the air spinning device
8 by winding the yarn Y onto the outer peripheral surface of the yarn storage roller
11a. This configuration enables more accurate control on the tension of the yarn Y.
Consequently, the yarn Y is generated by the air spinning device 8 at optimum spinning
tension, which can improve the quality of the yarn.
[0064] In this embodiment, the spinning machine 1 includes the core yarn supply device 7
having the package supporting unit 50 supporting the core yarn package CP with the
core yarn C wound thereon and the tension adding mechanism 70 adding tension to the
core yarn C unwound from the core yarn package CP. The unit controller 15 controls
the tension sensor 10 based on the tension measuring signal transmitted from the tension
sensor 10 such that the tension of the yarn Y detected in the tension adding mechanism
70 falls within a predetermined range. This configuration can improve the quality
of the yarn Y wound by the winding device 13.
[0065] Another embodiment will now be described. In the spinning machine 1 according to
another embodiment, as illustrated in FIG. 6, a bottom roller of the pair of front
rollers 19 (hereinafter may be referred to as a "front bottom roller" ) is driven
and rotated by a driving motor 20 installed in each spinning unit 2. A motor driver
20a controls driving of the driving motor 20. The motor driver 20a controls driving
of the driving motor 20 based on a signal output from the unit controller 15. The
bottom roller of each pair of back rollers 16, third rollers 17, and middle rollers
18 may be driven and rotated by the driving motor installed in each spinning unit
2 or may be driven and rotated by a driving motor installed in the second end frame
5.
[0066] A method of controlling the tension of the yarn Y with the pair of front rollers
19 will now be described.
[0067] When the spinning unit 2 of the spinning machine 1 starts the spinning operation,
the tension sensor 10 measures the tension of traveling yarn Y and transmits a tension
measuring signal to the unit controller 15. The unit controller 15 rotates the pair
of front rollers 19 of the drafting device 6 at the initial speed set for each lot.
The initial speed is preset such that the tension of the yarn Y detected by the tension
sensor 10 falls within a predetermined range.
[0068] The unit controller 15 receives the tension measuring signal and determines whether
the tension of the yarn Y indicated by the tension measuring signal falls within the
predetermined range. If the unit controller 15 determines that the tension of the
yarn Y is out of the predetermined range, the unit controller 15 controls the circumferential
speed of the pair of front rollers 19 (the front bottom roller). In this embodiment,
the unit controller 15 controls the tension of the yarn Y by changing the circumferential
speed of the front bottom roller without changing the number of rotations of the yarn
storage roller 11a. The drafting operation by the drafting device 6, the spinning
operation by the air spinning device 8, and the winding operation by the winding device
13 are continuing in parallel with the control.
[0069] Specifically, if the tension of the yarn Y is below the predetermined range, the
unit controller 15 decreases the circumferential speed of the pair of front rollers
19 from the initial speed. More specifically, the unit controller 15 outputs a signal
to the motor driver 20a of the driving motor 20 and decreases the number of rotations
(rpm) of the driving motor 20.
[0070] This process changes the feed ratio of the yarn Y determined based on the number
of rotations of the yarn storage roller 11a and the circumferential speed of the pair
of front rollers 19. Specifically, the speed of the yarn Y delivered from the pair
of front rollers 19 to the air spinning device 8 becomes lower than the speed of the
yarn Y drawn from the air spinning device 8 by the yarn storage roller 11a, which
changes the feed ratio of the yarn Y and accordingly increases the tension of the
yarn Y. When the unit controller 15 determines that the tension of the yarn Y has
increased to the predetermined range based on the tension measuring signal, the unit
controller 15 completes the control of decreasing the circumferential speed of the
front bottom roller and controls the circumferential speed of the front bottom roller
so that the tension of the yarn Y is maintained within the predetermined range.
[0071] If the tension of the yarn Y is beyond the predetermined range, the unit controller
15 increases the circumferential speed of the pair of front rollers 19 from the initial
speed. This operation makes the speed of the yarn Y delivered from the pair of front
rollers 19 to the air spinning device 8 higher than the speed of the yarn Y drawn
from the air spinning device 8 by the yarn storage roller 11a, which changes the feed
ratio of the yarn Y. The tension of the yarn Y decreases with the change in the feed
ratio. When the unit controller 15 determines that the tension of the yarn Y has decreased
to the predetermined range based on the tension measuring signal, the unit controller
15 completes the control of increasing the circumferential speed of the front bottom
roller and controls the circumferential speed of the front bottom roller so that the
tension of the yarn Y is maintained within the predetermined range.
[0072] In such a configuration that at least one of respective bottom rollers of the pair
of back rollers 16, the pair of third rollers 17, and the pair of middle rollers 18
is driven and rotated by the driving motor installed in each spinning unit 2, the
circumferential speed of at least the pair of back rollers 16, the pair of third rollers
17, or the pair of middle rollers 18 may be controlled in addition to the control
of the circumferential speed of the pair of front rollers 19.
[0073] In this embodiment, the unit controller 15 controls the circumferential speed of
the pair of front rollers 19 based on the tension measuring signal transmitted from
the tension sensor 10. The feed ratio changes with the change in the circumferential
speed of the pair of front rollers 19 of the drafting device 6. The change in the
feed ratio can change the tension of the fiber bundle F (the yarn Y) in the downstream
side from the pair of front rollers 19. Consequently, the spinning machine 1 can effectively
control the tension of the yarn Y by controlling the circumferential speed of the
pair of front rollers 19 based on the tension measuring signal transmitted from the
tension sensor 10.
[0074] Specifically, if the tension of the yarn Y is detected below a predetermined range
in the tension measuring signal, the unit controller 15 decreases the circumferential
speed of the pair of front rollers 19 from the initial speed until the tension of
the yarn Y increases to the predetermined range. If the tension of the yarn Y is detected
beyond the predetermined range in the tension measuring signal, the unit controller
15 increases the circumferential speed of the pair of front rollers 19 from the initial
speed until the tension of the yarn Y decreases to the predetermined range. The tension
of the yarn Y can be decreased by increasing the circumferential speed of the pair
of front rollers 19, whereas the tension of the yarn Y can be increased by decreasing
the circumferential speed of the pair of front rollers 19. The unit controller 15
controls the circumferential speed of the pair of front rollers 19 based on the tension
measuring signal and maintains the tension of the yarn Y within the predetermined
range.
[0075] The tension of the yarn Y may be controlled by controlling at least one of the drafting
device 6, the core yarn supply device 7, and the yarn storage device 11. In another
way, the tension of the yarn Y may be controlled by controlling both the pair of front
rollers 19 of the drafting device 6 and the yarn storage device 11. In still another
way, the tension of the yarn Y may be controlled by controlling both the pair of front
rollers 19 of the drafting device 6 and the tension adding mechanism 70 of the core
yarn supply device 7. Furthermore, the tension of the yarn Y may be controlled by
controlling these three devices, which are the pair of front rollers 19 of the drafting
device 6, the tension adding mechanism 70 of the core yarn supply device 7, and the
yarn storage roller 11a of the yarn storage device 11.
[0076] An embodiment has been described as above; however the embodiment is not limited
thereto.
[0077] In the above-described embodiment, the feedback control based on a result of detection
by the tension sensor 10 is provided in parallel with the winding operation of the
package P. If the tension of the yarn Y detected by the tension sensor 10 does not
fall within a predetermined range even with the feedback control over a certain period,
the spinning operation and the winding operation in the spinning unit 2 may be stopped.
In at least one of the drafting device 6, the yarn storage device 11, and the tension
adding mechanism 70, a limited range may be set for the amount (such as the number
of rotations of the pair of front rollers 19 and/or the yarn storage roller 11a and
the amount of tension added by the tension adding mechanism 70) to be controlled in
the feedback control. In this case, if the controlled amount is out of the limited
range, the spinning operation and the winding operation of the spinning unit 2 may
be stopped. When the spinning operation and the winding operation are stopped from
any of the above-described reasons, the display screen 102 and/or a display unit (not
illustrated) installed to each spinning unit 2 may make a display informing that an
error has been caused.
[0078] In the above-described embodiment, such a configuration has been described as an
example that the spinning unit 2 of the spinning machine 1 includes the core yarn
supply device 7; however, the core yarn supply device 7 may not be installed to the
spinning unit 2.
[0079] In the above-described embodiment, such a configuration has been described as an
example that the tension adding unit 71 of the tension adding mechanism 70 in the
core yarn supply device 7 adds tension to the yarn Y by bending the core yarn C a
plurality of times. In the tension adding mechanism 70, instead of controlling the
actuator 76, the tension added to the core yarn C by the tension adding unit 71 may
be adjusted by controlling the degree at which the movable piece 74 opens with respect
to the fixed piece 73 by electrically adjusting the contact angle of a spring (not
illustrated). The mechanism for adding tension to the core yarn C is not limited thereto.
As an example of mechanisms to add tension to the core yarn C, a yarn path of the
core yarn C may be bent with a disk. Tension may be added to the core yarn C in any
position in the upstream side from the core yarn guiding unit 52.
[0080] In the above-described embodiment, such an exemplary configuration has been described
that the tension sensor 10 measures the tension of traveling yarn Y between the air
spinning device 8 and the yarn storage device 11; however, the position of the tension
sensor 10 is not limited thereto. The tension sensor 10 may measure the tension of
the yarn Y at any position between the air spinning device 8 and the winding device
13.
[0081] In the above-described embodiment, the unit controller 15 serves as a control unit
controlling the yarn forming unit and the winding device 13 based on a result of detection
by the tension sensor 10 such that the yarn Y is wound with adjustment of the tension
added by the yarn forming unit. Instead of the unit controller 15, the machine control
device 100 may serve as the control unit.
[0082] The air spinning device 8 may further include a needle retained by the fiber guiding
unit and projecting into the spinning room so as to prevent twist of the fiber bundle
from spreading upstream of the air spinning device. In another case, instead of using
the needle, the air spinning device may prevent twist of the fiber bundle from spreading
upstream of the air spinning device using an end in the downstream side of the fiber
guiding unit. Instead of the above configuration, the air spinning device may include
a pair of air jet nozzles for twisting the fiber bundle in respective directions opposite
to each other. The spinning machine may be an open-end spinning machine.
[0083] In the spinning unit 2, the yarn storage device 11 has a function of drawing the
yarn Y from the air spinning device 8; however, the yarn Y may be drawn from the air
spinning device 8 by a delivery roller and a nip roller. In this case, the yarn storage
device 11 can be omitted. Furthermore, a slack tube absorbing slack of the yarn Y
with suction airflow, a mechanical compensator, or the like may replace the yarn storage
device 11. In a configuration using a delivery roller, the unit controller 15 controls
the circumferential speed of the delivery roller when the unit controller 15 determines
that the tension of the yarn Y is out of a predetermined range. The change in the
circumferential speed of the delivery roller changes the feed ratio of the yarn Y.
The change in the feed ratio can change the tension of the yarn Y drawn by the delivery
roller. Consequently, in the spinning machine, the tension of the yarn Y is controlled
by controlling the circumferential speed of the delivery roller based on a result
of detection by the tension sensor 10.
[0084] The devices in the spinning machine 1 are disposed in a manner that the yarn Y supplied
in the upper side are wound in the lower side in the height direction. The devices
may be disposed such that the yarn supplied in the lower side is wound in the upper
side.
[0085] In the spinning machine 1, the traverse guide 23 is driven by power from the second
end frame 5 (in other words, driven by power shared by a plurality of spinning units
2). Instead of this configuration, the devices (such as the air spinning device and
the winding device) of each spinning unit 2 may be driven on a per-spinning unit 2
basis.
[0086] Furthermore, the tension sensor 10 may be disposed upstream of the yarn monitoring
device 9 in a direction in which the yarn Y travels. The unit controller 15 may be
provided in each spinning unit 2. The yarn monitoring device 9 and the waxing device
12 may be omitted from each spinning unit 2.
[0087] FIG. 1 illustrates the spinning machine 1 winding the yarn into the package P in
a cheese-like shape; however, the spinning machine 1 can wind yarn into a package
in a corn-like shape. In the case with a package in a corn-like shape, although the
yarn traverse causes slack on the yarn, the slack can be absorbed by the yarn storage
device 11. Materials and shapes of the components are not limited to those described
above, and various materials and shapes may be employed. Instead of the spinning machine
1 including the air spinning device 8, a ring spinning frame may be usable. The ring
spinning frame is a spinning machine forming yarn from a fiber bundle (a spun material)
and winds the yarn onto a spinning bobbin. A yarn forming unit in the ring spinning
frame corresponds to the pair of front rollers of the drafting device and/or the tension
adding unit of the core yarn supply device. If a ring spinning frame is used as a
spinning machine, the ring spinning frame may include a core yarn supply device or
may not include the same. If the ring spinning frame includes a core yarn supply device,
a fiber bundle and/or core yarn are used as a spun material.
[0088] At least a part of the above-described embodiments may be combined as appropriate.
[0089] A spinning machine according to an embodiment of the present disclosure includes
a yarn forming unit forming yarn from a spun material while adjusting the tension
of the spun material, a winding device winding the yarn formed by the yarn forming
unit, a tension detecting unit detecting the tension of the yarn in the upstream side
from the winding device in a direction in which the yarn travels, and a control unit
controlling the yarn forming unit and the winding device based on a result of detection
by the tension detecting unit such that the yarn is wound with adjustment of the tension
added by the yarn forming unit.
[0090] A spinning machine according to an embodiment of the present disclosure can maintain
the tension of yarn within a predetermined range by providing feedback control to
devices based on the tension of the yarn detected by a tension detecting unit. The
spinning machine in this configuration can improve the quality of yarn.
[0091] A spinning machine according to an embodiment of the present disclosure includes
a core yarn supply device having a supporting unit supporting a core yarn package
with core yarn wound thereon and a tension adding unit adding tension to the core
yarn unwound from the core yarn package. A control unit may control the operation
of a yarn forming unit based on a result of detection by a tension detecting unit.
A winding device may wind yarn including core yarn. This configuration enables winding
of yarn while forming the yarn including core yarn with higher quality.
[0092] The following items also form part of the invention:
- 1. A spinning machine (1) comprising:
a yarn forming unit (6, 11a) configured to form yarn from a spun material;
a winding device (13) configured to wind the yarn formed by the yarn forming unit
(6, 11a) ;
a tension detecting unit (10) configured to detect tension of the yarn in an upstream
side from the winding device (13) in a direction in which the yarn travels; and
a control unit (15) configured to control the yarn forming unit (6, 11a) based on
a result of detection by the tension detecting unit (10) such that the yarn is wound
onto the winding device (13) with adjustment of tension added to the spun material
in the yarn forming unit (6, 11a), wherein
the control unit (15) adjusts the tension by controlling a device of the yarn forming
unit (6, 11a) disposed at least in an upstream side or a downstream side from a position
at which the spun material is twisted in the direction in which the yarn travels.
- 2. The spinning machine (1) according to 1, further comprising:
a drafting device (6) configured to draft a fiber bundle used as the spun material,
wherein
the drafting device (6) includes a plurality of pairs of rollers including a pair
of front rollers (19) disposed in a most downstream position in a direction in which
the fiber bundle is drafted, and
the control unit (15) controls a circumferential speed of the pair of front rollers
(19) based on the result of detection by the tension detecting unit (10).
- 3. The spinning machine (1) according to 2, wherein
when the tension of the yarn is detected below a predetermined range in the result
of detection, the control unit (15) provides control of decreasing a current circumferential
speed of the pair of front rollers (19) until the tension of the yarn increases to
the predetermined range, and
when the tension of the yarn is detected beyond the predetermined range in the result
of detection, the control unit (15) provides control of increasing a current circumferential
speed of the pair of front rollers (19) until the tension of the yarn decreases to
the predetermined range.
- 4. The spinning machine (1) according to any one of 1 to 3, wherein
the yarn forming unit includes a yarn storage roller (11a) disposed upstream of the
winding device (13) in the direction in which the yarn travels and configured to store
the yarn, and
the control unit (15) controls the number of rotations per unit time of the yarn storage
roller (11a) based on the result of detection by the tension detecting unit (10) such
that tension of the yarn detected by the tension detecting unit (10) falls within
the predetermined range.
- 5. The spinning machine (1) according to 4, wherein
when tension of the yarn is detected below a predetermined range in the result of
detection, the control unit (15) provides control of increasing the current number
of rotations of the yarn storage roller (11a) until the tension of the yarn increases
to the predetermined range, and
when tension of the yarn is detected beyond the predetermined range in the result
of detection, the control unit (15) provides control of decreasing the current number
of rotations of the yarn storage roller (11a) until the tension of the yarn decreases
to the predetermined range.
- 6. The spinning machine (1) according to 4 or 5, further comprising;
an air spinning device (7) configured to generate the yarn by applying swirling airflow
to a fiber bundle, wherein
the yarn storage roller (11a) stores the yarn while drawing the yarn generated by
the air spinning device (7).
- 7. A spinning machine (1) comprising:
a yarn forming unit including a core yarn supply device (7) that includes a supporting
unit (50) configured to support a core yarn package with core yarn wound thereon and
a tension adding unit (71) configured to add tension to the core yarn unwound from
the core yarn package, the yarn forming unit being configured to form yarn from a
spun material including the core yarn;
a winding device (13) configured to wind the yarn formed by the yarn forming unit;
a tension detecting unit (10) configured to detect tension of the yarn in an upstream
side from the winding device (13) in a direction in which the yarn travels; and
a control unit (15) configured to control the tension adding unit (71) based on a
result of detection by the tension detecting unit (10) such that the yarn is wound
onto the winding device (13) with adjustment of tension added to the spun material
in the yarn forming unit.
- 8. The spinning machine (1) according to 7, wherein the control unit (15) controls
the tension adding unit based on the result of detection by the tension detecting
unit (10) such that tension of the yarn detected by the tension detecting unit (10)
falls within a predetermined range.
1. A spinning machine (1) comprising:
a core yarn supply device (7) that includes a supporting unit (50) configured to support
a core yarn package with core yarn (C) wound thereon and a tension adding unit (71)
configured to add tension to the core yarn (C) unwound from the core yarn package;
a winding device (13) configured to wind yarn (4) formed from a fiber bundle including
the core yarn (C);
a tension detecting unit (10) configured to detect tension of the yarn (4) in an upstream
side from the winding device (13) in a direction in which the yarn (4) travels; and
a control unit (15) configured to control the tension adding unit (71) based on a
result of detection by the tension detecting unit (10) such that the yarn (4) is wound
onto the winding device (13) with adjustment of tension added to the core yarn (C)
in the core yarn supply device (7).
2. The spinning machine (1) according to claim 1, wherein the control unit (15) controls
the tension adding unit (71) based on the result of detection by the tension detecting
unit (10) such that the tension of the yarn (4) detected by the tension detecting
unit (10) falls within a predetermined range.
3. The spinning machine (1) according to claim 1 or 2, further comprising: a drafting
device (6) configured to draft a fiber bundle, and preferably further comprising an
air spinning device (8) configured to generate the yarn (4) by twisting the fiber
bundle drafted by the drafting device (6) using swirling airflow.
4. The spinning machine (1) according to any one of claims 1 to 3, wherein the tension
adding unit (71) includes a fixed piece (73) and a movable piece (74), with the core
yarn (C) alternately hooked to the fixed piece (73) and the movable piece (74), the
core yarn (C) being bent a plurality of times in the tension adding unit (71).
5. The spinning machine (1) according to claim 4, wherein the tension to be added to
the yarn (4) is adjusted by controlling the degree at which the movable piece (74)
opens with respect to the fixed piece (73).
6. The spinning machine (1) according to any one of claims 1 to 5, wherein the control
of the tension of the yarn (4) being additionally performed by controlling a pair
of front rollers (19) disposed in a most downstream position in a direction in which
the fiber bundle is drafted.
7. The spinning machine (1) according to claim 6, wherein
the control unit (15) controls a circumferential speed of the pair of front rollers
(19) based on the result of the detection by the tension detecting unit (10).
8. The spinning machine (1) according to claim 7, wherein
when the tension of the yarn (4) is detected below a predetermined range, the control
unit (15) provides control by decreasing a current circumferential speed of the pair
of front rollers (19) until the tension of the yarn (4) increases to the predetermined
range, and
when the tension of the yarn (4) is detected to be beyond the predetermined range,
the control unit (15) provides control by increasing a current circumferential speed
of the pair of front rollers (19) until the tension of the yarn (4) decreases to the
predetermined range.
9. The spinning machine (1) according to any one of claims 1 to 8,
further including a yarn storage roller (11a) disposed upstream of the winding device
(13) in the direction in which the yarn (4) travels and which is configured to store
the yarn (4), and
the control unit (15) controls the number of rotations per unit time of the yarn storage
roller (11a) based on the result of detection by the tension detecting unit (10) such
that the tension of the yarn (4) detected by the tension detecting unit (10) falls
within the predetermined range.
10. The spinning machine (1) according to claim 9, wherein
when the tension of the yarn (4) is detected to be below a predetermined range, the
control unit (15) provides control by increasing a current number of rotations of
the yarn storage roller (11a) until the tension of the yarn (4) increases to the predetermined
range, and
when the tension of the yarn (4) is detected to be beyond the predetermined range,
the control unit (15) provides control by decreasing the current number of rotations
of a yarn storage roller (11a) until the tension of the yarn (4) decreases to the
predetermined range.
11. The spinning machine (1) according to any one of claims 9 to 10, further including
a waxing device (12) disposed between the yarn storage roller (11a) and the winding
device (13).
12. The spinning machine (1) according to any one of claims 1 to 3, wherein the tension
of the yarn (4) is adjusted by bending a yarn path of the core yarn (C) with a disk.
13. The spinning machine (1) according to any one of the preceding claims, wherein the
core yarn supply device (7) forms part of a yarn forming unit, the yarn forming unit
being configured to form yarn (4) from a material including the core yarn (C).
14. The spinning machine (1) according to any one of the preceding claims, the spinning
machine (1) being configured so that, if the tension of the yarn (4) detected by the
tension detecting unit (10) does not fall within a predetermined range even with feedback
control over a certain period, spinning operation and winding operation are stopped.