BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an air-jet spinning
machine.
2. Description of the Related Art
An air-jet spinning machine including a draft
device adapted to draft a fiber bundle, and a pneumatic
spinning device adapted to produce a yarn by applying
twists to a fiber bundle drafted by the draft device
has been provided. Such an air-jet spinning machine is,
for example, described in Japanese Unexamined Patent
Publication No. 2011-38225.
15
BRIEF SUMMARY OF THE INVENTION
It was recognized that, when a spinning operation
is interrupted, the fiber bundle fed from the draft
device may accumulate between a roller pair closest to
20 the pneumatic spinning device (most downstream) in the
draft device and an inlet of the pneumatic spinning
device. In such a case, a driven roller configuring
the roller pair most downstream of the draft device may
rub against the accumulated fiber bundle, and wear.
25 It is an object of the present invention to
provide an air-jet spinning machine capable of
preventing the driven roller most downstream of the
draft device from being damaged at interruption of the
spinning operation. This object is achieved by an air-
30 jet spinning machine according to claim 1.
An air-jet spinning machine comprises: a draft
2 / 52
device including a first roller pair and a second
roller pair and adapted to draft a fiber bundle; a
pneumatic spinning device adapted to produce a yarn by
applying twists to the fiber bundle, fed from the first
5 roller pair, by a whirling flow of air; a withdrawal
device adapted to withdraw the yarn from the pneumatic
spinning device; a winding device adapted to wind the
yarn withdrawn by the withdrawal device; a detecting
device adapted to detect a presence or an absence of
10 the yarn; and a yarn joining device adapted to join the
yarn produced by the pneumatic spinning device and the
yarn wound by the winding device, wherein the first
roller pair includes a first driving roller and a first
driven roller; the second roller pair includes a second
15 driving roller and a second driven roller; the draft
device includes: a moving section adapted to move the
first driven roller between a contacting position and a
separated position, the contacting position being a
position where the first driven roller makes contact
20 with the first driving roller and the separated
position being a position where the first driven roller
is located away from the first driving roller and an
inlet of the pneumatic spinning device, and a draft
cradle adapted to cause the second driven roller to
25 make contact with the second driving roller; and the
moving section is adapted to move the first driven
roller to the separated position and the draft cradle
is adapted to maintain the second driven roller in
contact with the second driving roller, at an
30 interruption of an spinning operation of the yarn.
3 / 52
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of a spinning machine
according to one embodiment of the present invention;
FIG. 2 is a side view of a spinning unit of the
5 spinning machine of FIG. 1;
FIG. 3 is a cross-sectional view of a pneumatic
spinning device of FIG. 1;
FIG. 4 is a side view illustrating a structure of
a moving section and a periphery of the moving section
10 in a state a top roller is located at a contacting
position;
FIG. 5 is a top view illustrating a structure of
the moving section and the periphery of the moving
section;
15 FIG. 6 is a side view illustrating a structure of
the moving section and the periphery of the moving
section in a state the top roller is located at a
separated position;
FIG. 7 is a control block diagram of the spinning
20 unit; and
FIG. 8 is a side view of the spinning unit
according to an alternative embodiment.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT
25 An embodiment of the present invention will be
hereinafter described in detail with reference to the
accompanying drawings. The same reference numerals are
denoted on the same or corresponding portions
throughout the drawings, and redundant description will
30 be omitted.
As illustrated in FIG. 1, an air-jet spinning
4 / 52
machine 1 includes a plurality of spinning units 2, a
yarn joining cart 3, a doffing cart (not illustrated),
a first end frame 4, and a second end frame 5. The
plurality of the spinning units 2 are arranged in a row.
5 Each of the spinning units 2 is adapted to produce a
yarn Y and to wind the yarn Y around a package P. The
yarn joining cart 3 is adapted to perform a yarn
joining operation in a spinning unit 2 after the yarn Y
is cut, or is broken for some reason in such a spinning
10 unit 2. The doffing cart is adapted to doff a package
P and to supply a new bobbin B to a spinning unit 2
after the package P is fully-wound in such a spinning
unit 2. The first end frame 4 accommodates, for
example, a collecting device adapted to collect a fiber
15 waste, a yarn waste, and the like generated in the
spinning units 2.
The second end frame 5 accommodates an air
supplying section 5a (see FIG. 7) adapted to adjust
pressure of compressed air (air) to be supplied to each
20 section of the air-jet spinning machine 1 and to supply
the air to each section, a drive motor adapted to
supply power to each section of the spinning unit 2,
and the like. The second end frame 5 is provided with
a machine control device 41, a display screen 42, and
25 an input key 43. The machine control device 41 is
adapted to intensively manage and control each section
of the air-jet spinning machine 1. The display screen
42 is capable of displaying information relating to set
contents and/or status, or the like of the spinning
30 units 2. An operator can perform a setting operation
of the spinning units 2 by performing an appropriate
5 / 52
operation with the input key 43.
As illustrated in FIGS. 1 and 2, each spinning
unit 2 includes a draft device 6, a pneumatic spinning
device 7, a yarn monitoring device 8, a tension sensor
5 9, a yarn accumulating device (withdrawal device) 11, a
waxing device 12, and a winding device 13 in this order
from upstream in a travelling direction of the yarn Y.
A unit controller 10 is provided for every prescribed
number of the spinning units 2 and is adapted to
10 control operations of the spinning units 2. In the
present embodiment, an inlet of the draft device 6 is
arranged above the winding device 13 in a height
direction.
The draft device 6 is adapted to draft a sliver
15 (fiber bundle) S to produce a fiber bundle F. The
draft device 6 includes a back roller pair 14, a third
roller pair 15, a middle roller pair (second roller
pair) 16 and a front roller pair (first roller pair) 17
in this order from upstream in a travelling direction
20 of the sliver S. The back roller pair 14 includes a
bottom roller 14a and a top roller 14b. The third
roller pair 15 includes a bottom roller 15a and a top
roller 15b. The middle roller pair 16 includes a
bottom roller (second driving roller) 16a, and a top
25 roller (second driven roller) 16b. The front roller
pair 17 includes a bottom roller (first driving roller)
17a and a top roller (first driven roller) 17b. Each
bottom roller 14a, 15a, 16a, 17a is rotationally driven
by the drive motor provided in the second end frame 5
30 or by a drive motor provided in each spinning unit 2.
An apron belt 18b is provided with respect to the top
6 / 52
roller 16b of the middle roller pair 16. An apron belt
18a is provided with respect to the bottom roller 16a
of the middle roller pair 16.
The top rollers 14b, 15b, 16b are rotatably
5 supported by a draft cradle 65 arranged in the draft
device 6. The draft cradle 65 can be swung with a
swing shaft as a center to move to a position where the
top roller 14b, 15b, 16b is respectively pressed
against the bottom roller 14a, 15a, 16a, and a position
10 where the top roller 14b, 15b, 16b is respectively
separated from the bottom roller 14a, 15a, 16a. In
other words, the draft cradle 65 brings the top roller
14b, 15b, 16b into contact with the bottom roller 14a,
15a, 16a, respectively.
15 The top roller 17b is pressed against the bottom
roller 17a by a moving section 100 (see FIG. 4 ) . The
structure of the moving section 100 will be described
later. In other words, the top roller 17b is pressed
against the bottom roller 17a and moved away from the
20 bottom roller 17a independent from the other top
rollers 14b, 15b, 16b.
The draft device 6 drafts the sliver S by having
the sliver S travel from the back roller pair 14
through the third roller pair 15 and the middle roller
25 pair 16 and towards the front roller pair 17 to produce
the fiber bundle F.
The pneumatic spinning device 7 is adapted to
produce the yarn Y by applying twists to the fiber
bundle F, which has been fed from the front roller pair
30 17 of the draft device 6, with whirling flow of air.
More specifically, as illustrated in FIG. 3, the
7 / 52
pneumatic spinning device 7 includes a nozzle block 70
and a hollow guide shaft body 80. In the nozzle block
70, the whirling flow of air acts on the fiber bundle F
fed from the draft device 6 while the fiber bundle F is
5 guided inward. The fiber bundle F applied with twists
is passed through the hollow guide shaft body 80 and
fed to the outside. The generation and stopping of
whirling flow are controlled by the unit controller 10.
The nozzle block 70 includes a fiber guiding
10 section 71 and a whirling flow generating section 72.
The fiber guiding section 71 includes a guide hole 71a
adapted to guide the fiber bundle F fed from the draft
device 6. An end on the draft device 6 side of the
guide hole 71a is an inlet 7a of the sliver S. The
15 whirling flow generating section 72 includes a spinning
chamber 73 and a plurality of first nozzles 74. A
distal end portion 75a of a needle 75 held by the fiber
guiding section 71 is located in the spinning chamber
73.
20 In the spinning chamber 73, a back end of fibers
of the fiber bundle F introduced through the guide hole
71a is whirled by the whirling flow of air. In order
to generate the whirling flow in the spinning chamber
73, air is injected from the plurality of first nozzles
25 74 to the spinning chamber 73. In other words, air for
generating the whirling flow passes through the
plurality of first nozzles 74. An opening 72a is
provided in the whirling flow generating section 72 so
as to be continuous with the spinning chamber 73. The
30 opening 72a is formed in a frustoconical shape tapered
towards the upstream. The needle 75 prevents twists of
8 / 52
the fiber bundle F from being propagated towards the
upstream of the pneumatic spinning device 7.
An upstream end 80a of the hollow guide shaft
body 80 is formed in a frustoconical shape tapered
5 towards the upstream, and is arranged in the opening
72a of the whirling flow generating section 72 with a
gap therebetween. When a flange-shaped cap 87 attached
to the hollow guide shaft body 80 makes contact with a
frame-shaped holder 76 adapted to support the nozzle
10 block 70, the hollow guide shaft body 80 is positioned
with respect to the spinning chamber 73. The air
injected from the plurality of first nozzles 74 to the
spinning chamber 73 flows into a decompressing chamber
77 formed in the holder 76 through the gap formed
15 between the end 80a of the hollow guide shaft body 80
and the opening 72a of the whirling flow generating
section 72, and is discharged with fibers that did not
become the yarn Y.
The hollow guide shaft body 80 includes a passage
20 81 and a plurality of second nozzles 84. The passage
81 feeds (guides) the yarn Y (fibers whirled in the
spinning chamber 73) to the outside. The air is
injected from the plurality of second nozzles 84 to the
passage 81.
25 The passage 81 extends along a center axial line
of the hollow guide shaft body 80, and is formed to
spread from an inlet 82 towards an outlet 83. Air is
supplied to each second nozzle 84 through an air supply
path 86 and an air flow path 85.
30 In the pneumatic spinning device 7, the air is
injected from at least the plurality of second nozzles
9 / 52
84 to the passage 81 during a yarn discharge spinning
period. The fiber bundle F drafted by the draft device
6 is thereby fed to the spinning chamber 73 through the
guide hole 71a. Thereafter, the air is also injected
5 from the plurality of first nozzles 74 to the spinning
chamber 73. In the spinning chamber 73, the air flows
towards downstream (i.e., towards a gap formed between
the end 80a of the hollow guide shaft body 80 and the
opening 72a of the whirling flow generating section 72)
10 while whirling in one direction. Thus, the fiber
bundle F introduced to the spinning chamber 73 is fed
to the vicinity of the inlet 82 of the passage 81 while
being applied with loose false twists. Since the air
flows downstream (i.e., towards the outlet 83 of the
15 passage 81) while whirling in the other direction
opposite the one direction in the passage 81, the fiber
bundle F fed to the vicinity of the inlet 82 of the
passage 81 is passed through the passage 81 while being
spun to a fasciated yarn form, and guided out from the
20 outlet 83.
The yarn discharge spinning is the spinning
carried out at the start of or when resuming the
spinning. In other words, the yarn discharge spinning
is the spinning operation in which the supply of the
25 fiber bundle F to the pneumatic spinning device 7 is
started from a state the fiber bundle F is not being
fed from the draft device 6 to the pneumatic spinning
device 7, and the pneumatic spinning device 7 starts
the production of the yarn Y using the fiber bundle F.
30 During a normal spinning period in which the yarn Y fed
from the pneumatic spinning device 7 is wound into the
10 / 52
package P, the air is not injected from the second
nozzle 84 and the air is injected from the first nozzle
74.
An outlet sensor 51 is provided between the
5 pneumatic spinning device 7 and the yarn monitoring
device 8. The outlet sensor 51 detects a presence or
an absence of the yarn Y at the outlet of the yarn Y in
the pneumatic spinning device 7. The outlet sensor 51
may be omitted.
10 The yarn monitoring device 8 is adapted to
monitor information on the travelling yarn Y between
the pneumatic spinning device 7 and the yarn
accumulating device 11, and to detect a presence or an
absence of a yarn defect based on the information
15 acquired by the monitoring. When detecting the yarn
defect, the yarn monitoring device 8 transmits a yarn
defect detection signal to the unit controller 10. The
yarn monitoring device 8 detects a thickness
abnormality of the yarn Y and/or a foreign substance
20 included in the yarn Y, for example, as the yarn defect.
The yarn monitoring device 8 also detects yarn breakage
(when excessive tension is applied on the yarn Y thus
breaking the yarn Y ) , and the like. In other words,
the yarn monitoring device 8 detects a presence or an
25 absence of the yarn Y as well as a presence or an
absence of a yarn defect. The yarn monitoring device 8
may detect only one of the presence or the absence of
the yarn Y and the presence or the absence of the yarn
defect.
30 The tension sensor 9 is adapted to measure
tension of the travelling yarn Y between the pneumatic
11 / 52
spinning device 7 and the yarn accumulating device 11,
and to transmit a tension measurement signal to the
unit controller 10. When the yarn Y is absent, the
tension sensor 9 cannot measure the tension of the yarn
5 Y. Therefore, the tension sensor 9 can also detect the
presence or the absence of the yarn Y. When the unit
controller 10 determines a presence of an abnormality
based on a detection result of the yarn monitoring
device 8 and/or the tension sensor 9, the yarn Y is cut
10 in the spinning unit 2. Specifically, by stopping air
supply to the pneumatic spinning device 7 to interrupt
the production of the yarn Y, the yarn Y is cut.
Alternatively, the yarn Y may be cut with a cutter
separately provided.
15 The yarn accumulating device 11 is adapted to
eliminate the slackening of the yarn Y between the
pneumatic spinning device 7 and the winding device 13.
The yarn accumulating device 11 has a function of
stably withdrawing the yarn Y from the pneumatic
20 spinning device 7, a function of preventing the yarn Y
from slackening by accumulating the yarn Y fed from the
pneumatic spinning device 7 at the time of the yarn
joining operation or the like by the yarn joining
device 26, and a function of preventing variation in
25 the tension of the yarn Y at downstream of the yarn
accumulating device 11 from being propagated to the
pneumatic spinning device 7.
Specifically, the yarn accumulating device 11
includes a yarn accumulating roller 33, an electric
30 motor 34 for rotatably driving the yarn accumulating
roller 33, and a yarn hooking member 35. The yarn Y is
12 / 52
temporarily accumulated by being wound around an outer
peripheral surface of the yarn accumulating roller 33.
The yarn hooking member 35 is attached to a
downstream end of the yarn accumulating roller 33. The
5 yarn hooking member 35 is supported in a relatively
rotatable manner with respect to the yarn accumulating
roller 33. A permanent magnet is attached to one of
the yarn hooking member 35 and the yarn accumulating
roller 33, and a magnetic hysteresis material is
10 attached to the other one of the yarn hooking member 35
and the yarn accumulating roller 33. Such magnetic
means generates a torque against the relative rotation
of the yarn hooking member 35 with respect to the yarn
accumulating roller 33. Therefore, only when a force
15 greater than the torque is applied to the yarn hooking
member 35 (when a yarn tension greater than or equal to
a prescribed value is applied), the yarn hooking member
35 relatively rotates with respect to the yarn
accumulating roller 33, and the yarn Y wound around the
20 yarn accumulating roller 33 can be unwound. When a
force greater than the torque is not applied to the
yarn hooking member 35, the yarn accumulating roller 33
and the yarn hooking member 35 integrally rotate, and
the yarn Y is accumulated on the yarn accumulating
25 roller 33.
As described above, the yarn accumulating device
11 operates to unwind the yarn Y when the yarn tension
at the downstream increases, and stop the unwinding of
the yarn Y when the yarn tension decreases (when the
30 yarn Y starts to slacken). Thus, the yarn accumulating
device 11 can resolve the slackening of the yarn Y, and
13 / 52
apply an appropriate tension to the yarn Y. With the
yarn hooking member 35 operating to absorb variation in
the tension applied to the yarn Y between the yarn
accumulating device 11 and the winding device 13, as
5 described above, the variation in the tension can be
prevented from affecting the yarn Y from the pneumatic
spinning device 7 to the yarn accumulating device 11.
The yarn accumulating device 11 includes an
accumulation amount detection sensor 36, and an
10 excessive winding detection sensor 37. The
accumulation amount detection sensor 36 detects whether
or not a minimum required yarn Y is accumulated on the
yarn accumulating roller 33. The accumulation amount
detection sensor 36 can detect the presence or the
15 absence of the yarn Y at the yarn accumulating roller
33. The excessive winding detection sensor 37 detects
whether or not the yarn Y exceeding a predefined amount
is wound around the yarn accumulating roller 33.
The waxing device 12 is adapted to apply wax to
20 the yarn Y between the yarn accumulating device 11 and
the winding device 13. A yarn detection sensor 38
adapted to detect a presence or an absence of the yarn
Y is arranged between the waxing device 12 and the
winding device 13.
25 The winding device 13 is adapted to wind the yarn
Y withdrawn from the pneumatic spinning device 7 by the
yarn accumulating device 11 around a bobbin B to form
the package P. The winding device 13 includes a cradle
arm 21, a winding drum 22, and a traverse guide 23.
30 The cradle arm 21 is adapted to rotatably support the
bobbin B. The cradle arm 21 is swingably supported by
14 / 52
a supporting shaft 24 and is adapted to bring a surface
of the bobbin B or a surface of the package P into
contact with a surface of the winding drum 22 under
appropriate pressure. A drive motor (not illustrated)
5 provided in the second end frame 5 is adapted to
simultaneously drive the winding drums 22 each provided
in the plurality of the spinning units 2. Accordingly,
in each spinning unit 2, the bobbin B or the package P
is rotated in a winding direction. The traverse guide
10 23 of each spinning unit 2 is provided on a shaft 25
shared by the plurality of the spinning units 2. By
driving the shaft 25 to reciprocate in a rotation axis
direction of the winding drum 22 by the drive motor in
the second end frame 5, the traverse guide 23 traverses
15 the yarn Y in a prescribed width with respect to the
rotating bobbin B or package P.
The air-jet spinning machine 1 includes a
plurality of yarn joining carts 3. One yarn joining
cart 3 is provided for a plurality of (prescribed
20 number of) spinning units 2. Only one yarn joining
cart 3 may be provided in the air-jet spinning machine
1 depending on the number of spinning units 2 arranged
in the air-jet spinning machine 1. After the yarn Y is
cut or is broken for some reason in a spinning unit 2,
25 the yarn joining cart 3 travels to such a spinning unit
2 to perform the yarn joining operation. The yarn
joining cart 3 includes a yarn joining device 26, a
suction pipe 27, and a suction mouth 28. The suction
pipe 27 is swingably supported by a supporting shaft 31,
30 and is adapted to catch the yarn Y fed from the
pneumatic spinning device 7 and to guide the caught
15 / 52
yarn Y to the yarn joining device 26. The suction
mouth 28 is swingably supported by a supporting shaft
32, and is adapted to catch the yarn Y from the winding
device 13 and to guide the caught yarn Y to the yarn
5 joining device 26. The suction pipe 27 and the suction
mouth 28 catch the yarn Y by sucking. A suction sensor
39 is attached in the suction pipe 27. The suction
sensor 39 detects the presence or the absence of the
yarn Y sucked by the suction pipe 27. In other words,
10 the suction sensor 39 detects whether or not the yarn Y
is fed from the pneumatic spinning device 7.
The yarn joining device 26 is adapted to join the
guided yarns Y together. In other words, the yarn
joining device 26 joins the yarn Y produced by the
15 pneumatic spinning device 7 and the yarn Y wound by the
winding device 13. The yarn joining device 26 is a
splicer using the compressed air, a knotter adapted to
join the yarns Y together in a mechanical manner, or
the like. When the yarn joining cart 3 performs the
20 yarn joining operation, the package P is rotated in an
unwinding direction (reversely rotated). More
specifically, the cradle arm 21 is moved by a pneumatic
cylinder (not illustrated) such that the package P is
moved away from the winding drum 22, and the package P
25 is reversely rotated by a reversely-rotating roller
(not illustrated) provided in the yarn joining cart 3.
As described above, the outlet sensor 51, the
yarn monitoring device 8, the tension sensor 9, the
accumulation amount detection sensor 36, the yarn
30 detection sensor 38, and the suction sensor 39 function
as a detecting device adapted to detect a presence or
16 / 52
an absence of the yarn Y.
Next, description will be made on a structure of
the moving section 100 adapted to move the top roller
17b. As illustrated in FIGS. 4 to 6, the draft device
5 6 includes the moving section 100 adapted to move the
top roller 17b. The moving section 100 moves the top
roller 17b between a contacting position (state of FIG.
4) and a separated position (state of FIG. 6 ) , the
contacting position being a position where the top
10 roller 17b makes contact with the bottom roller 17a and
the separated position being a position where the top
roller 17b is located away from the bottom roller 17a
and the inlet 7a of the pneumatic spinning device 7.
In FIGS. 4 and 6, the pneumatic spinning device 7 is
15 indicated with a virtual line to illustrate the
structure of the moving section 100. In FIG. 5, a
frame 66 and a suction device 110 are omitted to
illustrate the structure of the moving section 100.
Specifically, the moving section 100 includes a
20 pneumatic cylinder (first pneumatic cylinder, second
pneumatic cylinder) 101, and a swinging portion 102.
The swinging portion 102 is attached to a fixing
portion 66a provided on the frame 66 in a manner to be
swingable about a shaft 103. One end of the swinging
25 portion 102 rotatably supports the top roller 17b. The
other end of the swinging portion 102 is coupled to the
pneumatic cylinder 101. The frame 66 is, for example,
a member adapted to support at least some devices of
each spinning unit 2.
30 The pneumatic cylinder 101 is configured to be
extended and retracted by the pressure of the supplied
17 / 52
air. The pneumatic cylinder 101 includes a rod portion
101a and a main body portion 101b. In the present
embodiment, the rod portion 101a of the pneumatic
cylinder 101 moves in a direction the pneumatic
5 cylinder 101 extends and in a direction the pneumatic
cylinder 101 retracts by the air pressure.
Specifically, two air supply tubes are connected to the
main body portion 101b. When air is supplied from one
air supply tube to the main body portion 101b, the rod
10 portion 101a moves with respect to the main body
portion 101b in the direction the pneumatic cylinder
101 extends. When air is supplied from the other air
supply tube to the main body portion 101b, the rod
portion 101a moves with respect to the main body
15 portion 101b in the direction the pneumatic cylinder
101 retracts.
As the pneumatic cylinder 101 is extended by air
pressure, the swinging portion 102 is swung with the
shaft 103 as the center and the top roller 17b is
20 brought into contact with the bottom roller 17a. The
front roller pair 17 drafts the sliver S under a state
in which the top roller 17b is located at the
contacting position. The pressure for pressing the top
roller 17b against the bottom roller 17a changes by the
25 pressure of the air supplied to the pneumatic cylinder
101. In the present embodiment, the pressure of the
air supplied to the pneumatic cylinder 101 is adjusted
so that the sliver S is sandwiched with the predefined
pressure at the front roller pair 17. As described
30 above, in the present embodiment, the moving section
100 also functions as a pressing section adapted to
18 / 52
press the top roller 17b against the bottom roller 17a.
When the moving section 100 functions as the pressing
section, the pneumatic cylinder 101 functions as a
second pneumatic cylinder adapted to press the top
5 roller 17b against the bottom roller 17a by extending.
As the pneumatic cylinder 101 is retracted by air
pressure, the swinging portion 102 is swung with the
shaft 103 as the center and the top roller 17b is moved
away from the bottom roller 17a. As described above,
10 the moving section 100 moves the top roller 17b to the
contacting position by extending the pneumatic cylinder
101, and moves the top roller 17b to the separated
position by retracting the pneumatic cylinder 101. The
moving section 100 may move the top roller 17b to the
15 contacting position by retracting the pneumatic
cylinder 101, and move the top roller 17b to the
separated position by extending the pneumatic cylinder
101. When the moving section 100 functions as the
pressing section in such a structure, the pneumatic
20 cylinder 101 functions as the second pneumatic cylinder
adapted to press the top roller 17b against the bottom
roller 17a by retracting.
The moving section 100 is provided for each of
the draft devices 6 of the plurality of spinning units
25 2 arranged in the air-jet spinning machine 1. The
moving section 100 arranged for each spinning unit 2
moves the top roller 17b between the contacting
position and the separated position independently of
one another. The moving section 100 arranged for each
30 spinning unit 2 presses the top roller 17b against the
bottom roller 17a independently of one another.
19 / 52
The spinning unit 2 further includes the suction
device 110. The suction device 110 includes a main
body portion 111, a suction nozzle 112, and a flexible
portion 113. The main body portion 111 is a hollow
5 shaped member, and is fixed to the swinging portion 102.
The suction nozzle 112 extends from the main body
portion 111 towards the proximity of the top roller 17b.
A suction port 112a is provided at a distal end portion
of the suction nozzle 112. The suction port 112a is
10 provided with respect to the top roller 17b. One end
of the flexible portion 113 is connected to the main
body portion 111. The other end of the flexible
portion 113 is connected to a suction tube, and the
like leading to the collecting device arranged in the
15 first end frame 4. The flexible portion 113 is, for
example, an accordion shaped tube, and has flexibility.
The suction device 110 is fixed to the swinging
portion 102 of the moving section 100. The suction
device 110 moves accompanying the movement of the top
20 roller 17b. The suction device 110 is provided for
each of the plurality of spinning units 2 arranged in
the air-jet spinning machine 1.
Next, an operation timing of the moving section
100 will be described. In the present embodiment, as
25 illustrated in FIG. 7, the operation of the moving
section 100 is controlled by the unit controller 10.
Specifically, the unit controller 10 controls the
supply of compressed air from the air supplying section
5a of the second end frame 5 to the pneumatic cylinder
30 101. The top roller 17b is moved between the
contacting position and the separated position by the
20 / 52
unit controller 10 controlling the supply of compressed
air to the pneumatic cylinder 101.
The unit controller 10 moves the top roller 17b
from the contacting position to the separated position
5 by means of the moving section 100 at the interruption
of the spinning operation of the yarn Y. The
interruption of the spinning operation is when the
spinning operation of the yarn Y in the pneumatic
spinning device 7 and the winding of the yarn Y in the
10 winding device 13 cannot be carried out. For example,
the interruption of the spinning operation is when the
yarn Y is not fed from the pneumatic spinning device 7
or when the yarn Y is cut or the Y is broken for some
reason. The spinning operation is also interrupted
15 when the package P is fully wound. Furthermore, the
spinning operation is also interrupted when the power
of the spinning unit 2 or the air-jet spinning machine
1 is turned OFF, when performing maintenance, and the
like. During a period in which the spinning operation
20 is interrupted, the draft operation of the draft device
6 and the winding operation of the winding device 13
are also interrupted.
The unit controller 10 moves the top roller 17b
from the contacting position to the separated position
25 by means of the moving section 100 based on the
detection results of the outlet sensor 51, the yarn
monitoring device 8, the tension sensor 9, the
accumulation amount detection sensor 36, the yarn
detection sensor 38, and the suction sensor 39. Even
30 if the moving section 100 moves the top roller 17b to
the separated position at the interruption of the
21 / 52
spinning operation, the top roller 14b, 15b, 16b
remains contacting the bottom roller 14a, 15a, 16a
until the draft cradle 65 is operated by the operator,
and the like.
5 The moving section 100 starts moving the top
roller 17b to the separated position while the top
roller 17b is rotating. In other words, the unit
controller 10 moves the top roller 17b to the separated
position before the rotation of the top roller 17b
10 completely stops after the interruption of the spinning
operation.
First, the control of the moving section 100 at
the start of the yarn discharge spinning will be
described. After the start of the yarn discharge
15 spinning (after start of injection of air from the
second nozzle 84), the yarn Y fed from the pneumatic
spinning device 7 is caught by the suction pipe 27 of
the yarn joining cart 3 and guided to the yarn joining
device 26. When the yarn discharge spinning fails, the
20 yarn Y is not fed from the pneumatic spinning device 7,
and the yarn Y is not caught by the suction pipe 27.
Thus, when the pneumatic spinning device 7 fails in the
yarn discharge spinning, the unit controller 10 moves
the top roller 17b from the contacting position to the
25 separated position by means of the moving section 100.
Specifically, when the output sensor 51 does not detect
the yarn Y within a prescribed time from the start of
the yarn discharge spinning, the unit controller 10
moves the top roller 17b to the separated position.
30 When the suction sensor 39 provided in the
suction pipe 27 does not detect the yarn Y within a
22 / 52
prescribed time from the start of the yarn discharge
spinning, the unit controller 10 may move the top
roller 17b to the separated position. When the
accumulation amount detection sensor 36 does not detect
5 the yarn Y within a prescribed time from the start of
the yarn discharge spinning, the unit controller 10 may
move the top roller 17b to the separated position.
When the yarn monitoring device 8 does not detect the
yarn Y within a prescribed time from the start of the
10 yarn discharge spinning, the unit controller 10 may
move the top roller 17b to the separated position. In
the present embodiment, the failure of the yarn
discharge spinning is detected early in the order of
the outlet sensor 51, the suction sensor 39, the
15 accumulation amount detection sensor 36, and the yarn
monitoring device 8.
Next, the control of the moving section 100 when
the yarn Y breaks during the spinning operation will be
described. A case in which the yarn Y breaks during
20 the spinning operation is a case in which the yarn Y is
no longer detected by the outlet sensor 51 and the like
while the pneumatic spinning device 7 is producing the
yarn Y (during normal spinning period). When the yarn
Y is no longer detected by at least one of the output
25 sensor 51, the yarn monitoring device 8, the tension
sensor 9, the accumulation amount detection sensor 36,
and the yarn detection sensor 38 during the spinning
operation by the spinning unit 2, the unit controller
10 moves the top roller 17b from the contacting
30 position to the separated position by means of the
moving section 100. When the yarn Y is not detected,
23 / 52
the unit controller 10 interrupts the production
(spinning operation) of the yarn Y by the pneumatic
spinning device 7.
Next, the control of the moving section 100 when
5 a yarn defect is detected by the yarn monitoring device
8 during the spinning operation will be described.
When the yarn defect is detected by the yarn monitoring
device 8 and the unit controller 10 determines that the
abnormality is present, the yarn Y is cut. In other
10 words, when the yarn defect is detected by the yarn
monitoring device 8 and the detected yarn defect is a
yarn defect that needs to be removed by cutting the
yarn Y, the unit controller 10 moves the top roller 17b
from the contacting position to the separated position
15 by means of the moving section 100. When the yarn
defect is detected and the detected yarn defect is a
yarn defect that needs to be removed by cutting the
yarn Y, the unit controller 10 interrupts the
production (spinning operation) of the yarn Y by the
20 pneumatic spinning device 7 and cuts the yarn Y.
As described above, in the air-jet spinning
machine 1 of the present embodiment, the top roller 17b
is moved to the separated position by the moving
section 100 at the interruption of the spinning
25 operation. In other words, even if the fiber bundle F
fed from the draft device 6 at the same time as the
interruption or immediately after the interruption of
the spinning operation is accumulated in the vicinity
of the inlet 7a of the pneumatic spinning device 7, the
30 top roller 17b is prevented from rubbing against the
accumulated fiber bundle F as the top roller 17b is
24 / 52
located at the separated position. Thus, the air-jet
spinning machine 1 can prevent the driven roller (top
roller 17b), which is located most downstream of the
draft device 6 and on the pneumatic spinning device 7
5 side, from being damaged at the same time as the
interruption or after the interruption of the spinning
operation.
The pneumatic spinning device 7 includes the
first nozzle 74 through which air for generating the
10 whirling flow in the spinning chamber 73 passes, and
the second nozzle 84 through which air injected to the
passage 81 for guiding the fibers whirled in the
spinning chamber 73 to the outside passes. In such a
case, the pneumatic spinning device 7 can produce the
15 yarn Y by the whirling flow. The pneumatic spinning
device 7 can carry out the yarn discharge spinning by
injecting air at least from the second nozzle 84.
When the outlet sensor 51 and the like do not
detect the yarn Y within a prescribed time from the
20 start of the yarn discharge spinning, the moving
section 100 moves the top roller 17b from the
contacting position to the separated position. A case
in which the outlet sensor 51 and the like do not
detect the yarn Y within a prescribed time from the
25 start of the yarn discharge spinning is a case in which
the pneumatic spinning device 7 fails in the yarn
discharge spinning. When the yarn discharge spinning
fails, the fiber bundle F is fed from the draft device
6 towards the pneumatic spinning device 7 until the
30 draft operation of the draft device 6 is stopped. Thus,
the fiber bundle F may accumulate in the vicinity of
25 / 52
the inlet 7a of the pneumatic spinning device 7. By
moving the top roller 17b to the separated position by
the moving section 100 when the yarn discharge spinning
fails, the top roller 17b can be prevented from being
5 damaged. When the yarn discharge spinning is
successful, the spinning operation by the pneumatic
spinning device 7, and the like are continued.
When the outlet sensor 51 and the like do not
detect the yarn Y during the production of the yarn Y
10 in the pneumatic spinning device 7, the pneumatic
spinning device 7 stops the production of the yarn Y,
and the moving section 100 moves the top roller 17b
from the contacting position to the separated position.
The movement of the top roller 17b to the separated
15 position may be started at the same time as the
stopping of the production of the yarn Y. When the
outlet sensor 51 and the like cannot detect the yarn Y
due to yarn breakage, and the like, the top roller 17b
is caused to move to the separated position. The fiber
20 bundle F may accumulate in the vicinity of the inlet 7a
of the pneumatic spinning device 7 depending on the
situation of the yarn breakage. Even in such a case,
the top roller 17b can be prevented from being damaged
by moving the top roller 17b to the separated position
25 by the moving section 100.
When the yarn monitoring device 8 detects a yarn
defect during the production of the yarn Y in the
pneumatic spinning device 7, the moving section 100
moves the top roller 17b from the contacting position
30 to the separated position. When the yarn defect is
detected, the defective portion of the yarn Y is
26 / 52
removed, and then the yarn joining operation is carried
out by the yarn joining device 26. The fiber bundle F
fed from the draft device 6 when the yarn Y is cut or
immediately thereafter due to the detection of the yarn
5 defect may accumulate in the vicinity of the inlet 7a
of the pneumatic spinning device 7. Even in such a
case, the top roller 17b can be prevented from being
damaged by moving the top roller 17b to the separated
position by the moving section 100.
10 The moving section 100 moves the top roller 17b
to the separated position under a state in which the
top roller 17b is rotating. In other words, the moving
section 100 rapidly moves the top roller 17b to the
separated position before the supply of the fiber
15 bundle F to the pneumatic spinning device 7 completely
stops. Thus, the air-jet spinning machine 1 can
prevent the top roller 17b from being damaged by the
accumulation of the fiber bundle F even if the draft
device 6 is feeding the fiber bundle F to the pneumatic
20 spinning device 7 at high speed.
The moving section 100 moves the top roller 17b
to the separated position by retracting the pneumatic
cylinder 101. Generally, the pneumatic cylinder that
is extended and retracted by the pressure of the
25 supplied air can be rapidly extended and retracted by
increasing the air pressure. Thus, the moving section
100 can rapidly move the top roller 17b to the
separated position using the pneumatic cylinder 101.
The air-jet spinning machine 1 includes a
30 plurality of spinning units 2. The moving section 100
of the draft device 6 in each of the plurality of
27 / 52
spinning units 2 moves the top roller 17b to the
separated position independently. In such a case, the
air-jet spinning machine 1 can move a top roller 17b of
a desired spinning unit 2 to the separated position
5 without influencing the spinning operation of the other
spinning units 2. For example, the air-jet spinning
machine 1 can carry out the replacement work and the
like of a top roller 17b of a desired spinning unit 2
while the spinning operation of the other spinning
10 units 2 is continuing.
The moving section 100 of the draft device 6 of
each of the plurality of spinning units 2 also serves
as a pressing section adapted to press the top roller
17b against the bottom roller 17a. In such a case, the
15 draft device 6 can sandwich the fiber bundle F in a
pressed state with the front roller pair 17, and can
draft the fiber bundle F without slipping at the front
roller pair 17. Furthermore, the air-jet spinning
machine 1 can press a top roller 17b of a desired
20 spinning unit 2 against a bottom roller 17a
irrespective of the pressed state of the draft device 6
of the other spinning units 2. In other words, even if
the top roller 17b in another spinning unit 2 is
located at the separated position, the spinning
25 operation can continue in the desired spinning unit 2.
The moving section 100 presses the top roller 17b
against the bottom roller 17a using the pneumatic
cylinder 101. In such a case, the moving section 100
can easily change the pressure at which the top roller
30 17b is pressed, by adjusting the pressure of the air to
be supplied to the pneumatic cylinder 101.
28 / 52
The suction device 110 attached to the moving
section 100 is arranged in each of the plurality of
spinning units 2. In such a case, the air-jet spinning
machine 1 can suck the fibers attached to the
5 respective top roller 17b and the like of the spinning
unit 2 with the suction device 110 arranged in each
spinning unit 2. Furthermore, the air-jet spinning
machine 1 can move the suction device 110 accompanying
the movement of the top roller 17b to the separated
10 position by the moving section 100.
Next, description on an alternative embodiment
will be made. The air-jet spinning machine 1 according
to the present alternative embodiment includes a
plurality of spinning units 2A illustrated in FIG. 8 in
15 place of the spinning units 2 illustrated in FIG. 2 and
the like. The spinning unit 2A illustrated in FIG. 8
includes the same devices as the spinning unit 2 along
the travelling direction of the yarn Y. In the
spinning unit 2A, the inlet of the draft device 6 is
20 located below the winding device 13 in the height
direction. The spinning unit 2A has a different
travelling direction of the yarn Y from the draft
device 6 to the winding device 13 with respect to the
spinning unit 2. Each device in the spinning unit 2A
25 is the same as each device in the spinning unit 2
described using FIG. 2 and the like, and same reference
numerals as each device in the spinning unit 2 are
denoted and detailed description will be omitted.
Each device arranged in the spinning unit 2A is
30 attached to a frame 67. The spinning unit 2A includes
a case storing section 68 adapted to be able to store a
29 / 52
sliver case SC accommodating the sliver S. The case
storing section 68 is configured by a space portion
formed with the frame 67. The sliver case SC is
located below the draft device 6 and the pneumatic
5 spinning device 7 in the height direction. The sliver
case SC is stored in the case storing section 68. The
sliver S accommodated in the sliver case SC is supplied
to the draft device 6 by way of a sliver guide (not
illustrated).
10 In the present alternative embodiment, the yarn
joining device 26 adapted to carry out the yarn joining
operation, the suction pipe 27, and the suction mouth
28 are arranged in respective spinning units 2A.
However, the air-jet spinning machine 1 may include a
15 plurality of yarn joining carts 3 in the present
alternative embodiment as well, similar to the
embodiment. One yarn joining cart 3 (yarn joining
device 26) may be provided for a plurality of spinning
units 2A. Only one yarn joining cart 3 may be provided
20 in the air-jet spinning machine 1 depending on the
number of spinning units 2A.
In the present alternative embodiment as well,
the draft device 6 includes the moving section 100
adapted to move the top roller 17b, similar to the
25 embodiment. Operation effects similar to the
embodiment can also be obtained in the air-jet spinning
machine 1 including the spinning unit 2A according to
the present alternative embodiment. Furthermore, in
the present alternative embodiment, the inlet of the
30 draft device 6 is located below the winding device 13
in the height direction. In such a case, the air-jet
30 / 52
spinning machine 1 can wind the produced yarn Y while
having the fiber bundle F and the yarn Y to travel from
the lower side towards the upper side in the height
direction.
5 The embodiments of the present invention have
been described above, but the present invention is not
limited to the above embodiments.
The moving section 100 also serves as the
pressing section adapted to press the top roller 17b
10 against the bottom roller 17a, but the air-jet spinning
machine 1 may include a pressing section separate from
the moving section 100. For example, the air-jet
spinning machine 1 may include a spring as the pressing
section. The top roller 17b may be pressed against the
15 bottom roller 17a by the elastic force of the spring.
When the spring is provided as the pressing section,
the pressing section can press the top roller 17b
against the bottom roller 17a without receiving supply
of air, and the like.
20 The moving section 100 may include a lever
adapted to move the top roller 17b to the separated
position. The lever may be operated by an operator.
The moving section 100 can move the top roller 17b to
the separated position at, for example, timing desired
25 by the operator operating the lever. When the lever is
arranged on the moving section 100, the pneumatic
cylinder 101 for moving the top roller 17b may not be
provided. Alternatively, the lever may be arranged on
the moving section 100, in addition to the pneumatic
30 cylinder 101. In such a case, apart from the top
roller 17b being moved by the pneumatic cylinder 101 at
31 / 52
the interruption of the spinning operation, for example,
the top roller 17b can be moved to the separated
position by the lever being operated by the operator
and the like for maintenance work and the like. As
5 described above, the moving section 100 may function as
the pressing section, and the top roller 17b may be
pressed against the bottom roller 17a by the extension
or retraction of the pneumatic cylinder 101. In this
case, when the lever is operated by the operator and
10 the like, the supply of air to the pneumatic cylinder
101 is preferably stopped. Furthermore, the lever
arranged on the moving section 100 may be configured to
move the top roller 17b from the separated position to
the contacting position when the lever is operated.
15 The lever arranged on the moving section 100 is not
limited to being operated by the operator, and may be
operated by at least one of another device arranged in
the spinning unit 2, 2A, the yarn joining cart 3, and a
robot.
20 The presence or the absence of failure of the
yarn discharge spinning may be determined based on a
detection result of a sensor arranged in a doffing cart.
The doffing cart includes a suction nozzle (guiding
section) adapted to catch the yarn Y fed from the
25 pneumatic spinning device 7 at the time of yarn
discharge spinning, and guide the yarn Y to a new
bobbin B supplied to the spinning unit 2. For example,
such doffing cart may guide the yarn Y caught with the
suction nozzle to the new bobbin B at the same time as
30 the supply of the new bobbin B to the spinning unit 2
or after the supply of the new bobbin B. A sensor
32 / 52
(detecting device) adapted to detect a presence or an
absence of the sucked yarn Y may be arranged with
respect to the suction nozzle of the doffing cart. In
this case, the presence or the absence of failure of
5 the yarn discharge spinning may be determined based on
the detection result of the sensor, similar to the
outlet sensor 51 and the like.
The air-jet spinning machine 1 in the embodiment
may include a service vehicle adapted to supply a new
10 bobbin B, around which the yarn Y is not wound, to the
spinning unit 2, in place of the doffing cart. The
service vehicle includes a suction nozzle (guiding
section) adapted to catch the yarn Y fed from the
pneumatic spinning device 7 at the time of yarn
15 discharge spinning, and guide the yarn Y to the new
bobbin B. A sensor (detecting device) adapted to
detect a presence or an absence of the sucked yarn Y is
arranged with respect to the suction nozzle of the
service vehicle. In this case, the presence or the
20 absence of failure of the yarn discharge spinning may
be determined based on the detection result of the
sensor, similar to the outlet sensor 51 and the like.
The yarn joining device 26 adapted to carry out
the yarn joining operation, the suction pipe 27, and
25 the suction mouth 28 may be arranged with respect to
the respective spinning unit 2 in the embodiment,
similar to the alternative embodiment.
In the embodiment and the alternative embodiment,
the draft device 6 may move the top roller 17b from the
30 separated position to the contacting position, and then
rotate the front roller pair 17 in a direction opposite
33 / 52
the draft direction before resuming the draft operation.
The fiber waste clogged at the inlet of the pneumatic
spinning device 7 thus can be withdrawn. The withdrawn
fiber waste may be sucked by a suction hole (not
5 illustrated) provided between the bottom roller 17a and
the pneumatic spinning device 7. Thereafter, the draft
operation by the draft device 6, the spinning operation
by the pneumatic spinning device 7 and the like are
resumed.
10 In the embodiment and the alternative embodiment,
the yarn monitoring device 8 is arranged upstream of
the yarn accumulating device 11, but the yarn
monitoring device 8 may be arranged downstream of the
yarn accumulating device 11. Furthermore, in the
15 embodiment and the alternative embodiment, various
detecting devices such as the outlet sensor 51 are
arranged, but only the yarn monitoring device 8 may be
arranged at the position of the waxing device 12. In
such a case, the presence or the absence of the yarn Y
20 is determined based on the detection result of the yarn
monitoring device 8.
All or at least one of the outlet sensor 51, the
tension sensor 9, the suction sensor 39, and the
accumulation amount detection sensor 36 may be omitted.
25 When the outlet sensor 51 is arranged, the suction
sensor 39 may be omitted. When the suction sensor 39
is arranged, the outlet sensor 51 may be omitted. The
detection result of the accumulation amount detection
sensor 36 may not be used for the control of the moving
30 section 100 and may be used only for the control of the
rotation of the yarn accumulating roller 33. The
34 / 52
failure of the yarn discharge spinning may be detected
based on all the detection results of the yarn
monitoring device 8, the outlet sensor 51, the suction
sensor 39, and the accumulation amount detection sensor
5 36. The failure of the yarn discharge spinning may be
detected based on at least one of the yarn monitoring
device 8, the outlet sensor 51, the suction sensor 39,
and the accumulation amount detection sensor 36.
In place of the needle 75, the pneumatic spinning
10 device 7 may prevent the twists of the fiber bundle F
from being propagated to upstream of the pneumatic
spinning device 7 by a downstream end portion of the
fiber guiding section 71. Furthermore, instead of the
above-described configuration, the pneumatic spinning
15 device 7 may include a pair of air-jet nozzles
respectively adapted to twist the fiber bundle F in
directions opposite from each other.
In the spinning unit 2, 2A, the yarn accumulating
device 11 has a function of withdrawing the yarn Y from
20 the pneumatic spinning device 7, but the yarn Y may be
withdrawn from the pneumatic spinning device 7 with a
delivery roller and a nip roller. In a case of
withdrawing the yarn Y from the pneumatic spinning
device 7 with the delivery roller and the nip roller, a
25 slack tube adapted to absorb the slackening of the yarn
Y with suction airflow, and/or a mechanic compensator
or the like may be provided instead of the yarn
accumulating device 11.
In the air-jet spinning machine 1, at least one
30 of the bottom rollers in the draft device 6 and the
traverse guides 23 are driven by power from the second
35 / 52
end frame 5 (that is, common among the plurality of
spinning units 2, 2A). However, each section (for
example, the draft device 6, the pneumatic spinning
device 7, the winding device 13, or the like) of the
5 spinning unit 2, 2A may be driven independently for
each spinning unit 2, 2A.
In the travelling direction of the yarn Y, the
tension sensor 9 may be arranged upstream of the yarn
monitoring device 8. The unit controller 10 may be
10 provided for each spinning unit 2, 2A. In the spinning
unit 2, the waxing device 12, the tension sensor 9, and
the yarn monitoring device 8 may be omitted.
FIG. 1 illustrates the air-jet spinning machine 1
so as to wind a cheese package P, but the air-jet
15 spinning machine 1 can also wind a conical package P.
In a case of the conical package, the slackening of a
yarn Y occurs by traversing the yarn Y, but the
slackening can be absorbed with the yarn accumulating
device 11. A material and a shape of each component
20 are not limited to the above-mentioned material and
shape, and various materials and shapes can be adopted.
In the embodiment described above, an example has
been described in which the draft device 6 includes the
back roller pair 14, the third roller pair 15, the
25 middle roller pair 16, and the front roller pair 17.
However, the front roller pair (roller pair arranged at
the position closest to the pneumatic spinning device
in a transportation path of the fiber bundle) may be
configured as a part of another device. For example,
30 the spinning unit may include a supplying device
adapted to supply the fiber bundle drafted with the
36 / 52
draft device to the pneumatic spinning device, and the
front roller pair may be included as one part of the
supplying device. The front roller pair may be
included in the draft device adapted to draft the fiber
5 bundle or the supplying device adapted to supply the
fiber bundle to the pneumatic spinning device, or may
be provided alone without being included in another
device.
The spinning unit 2, 2A may be configured to
10 carry out a warm-up operation. In this case, the draft
device 6 is operated under a state in which the sliver
S (fiber bundle F) is not set in the draft device 6.
Specifically, when a warm-up operation instructing
button (not illustrated) provided on the air-jet
15 spinning machine 1 and/or spinning unit 2, 2A is
operated, the front top roller 17a is moved to the
contacting position and the draft device 6 is idled.
After the warm-up operation is finished, the moving
section 100 may move the front top roller 17a to the
20 separated position.
An air-jet spinning machine according to the
present invention includes a draft device including a
first roller pair and a second roller pair and adapted
to draft a fiber bundle; a pneumatic spinning device
25 adapted to produce a yarn by applying twists to the
fiber bundle, fed from the first roller pair, by
whirling flow of air; a withdrawal device adapted to
withdraw the yarn from the pneumatic spinning device; a
winding device adapted to wind the yarn withdrawn by
30 the withdrawal device; a detecting device adapted to
detect a presence or an absence of the yarn; and a yarn
37 / 52
joining device adapted to join the yarn produced by the
pneumatic spinning device and the yarn wound by the
winding device, wherein the first roller pair includes
a first driving roller and a first driven roller; the
5 second roller pair includes a second driving roller and
a second driven roller; the draft device includes a
moving section adapted to move the first driven roller
between a contacting position and a separated position,
the contacting position being a position where the
10 first driven roller makes contact with the first
driving roller and the separated position being a
position where the first driven roller is located away
from the first driving roller and an inlet of the
pneumatic spinning device, and a draft cradle adapted
15 to cause the second driven roller to make contact with
the second driving roller; and the moving section is
adapted to move the first driven roller to the
separated position and the draft cradle is adapted to
maintain the second driven roller in contact with the
20 second driving roller at an interruption of an spinning
operation of the yarn.
In such an air-jet spinning machine, the first
driven roller is located at the separated position at
the interruption of the spinning operation. In other
25 words, even if the fiber bundle fed from the draft
device at the same time as the interruption or
immediately after the interruption of the spinning
operation is accumulated in the vicinity of the inlet
of the pneumatic spinning device, the first driven
30 roller is prevented from being rubbed against the
accumulated fiber bundle as the first driven roller is
38 / 52
located at the separated position. Thus, the air-jet
spinning machine can prevent the driven roller most
downstream of the draft device from being damaged at
the same time as the interruption or after the
5 interruption of the spinning operation.
The pneumatic spinning device may include a fiber
guiding section adapted to guide the fiber bundle fed
from the draft device, a nozzle block including a
spinning chamber in which fibers of the fiber bundle
10 guided by the fiber guiding section are whirled by the
whirling flow, and a first nozzle through which air for
generating the whirling flow passes, and a hollow guide
shaft body including a passage adapted to guide the
fibers whirled in the spinning chamber to outside, and
15 a second nozzle through which air to be injected into
the passage passes, wherein during yarn discharge
spinning in which production of the yarn is started
from a state in which the fiber bundle is not fed from
the draft device, the air may be injected from at least
20 the second nozzle, and the fiber bundle drafted by the
draft device may be fed into the spinning chamber from
the fiber guiding section. In such a case, in the airjet
spinning machine adapted to produce the yarn by the
whirling flow, a draft speed is high speed (compared to
25 a ring spinning machine), and thus even if the yarn
discharge spinning fails and the spinning operation is
interrupted, for example, the driven roller most
downstream of the draft device can be particularly
prevented from being damaged.
30 The moving section may be adapted to move the
first driven roller from the contacting position to the
39 / 52
separated position when the detecting device does not
detect the yarn within a prescribed period of time from
start of the yarn discharge spinning. A case in which
the detecting device does not detect the yarn within a
5 prescribed period of time from the start of the yarn
discharge spinning is a case in which the pneumatic
spinning device fails in the yarn discharge spinning.
When the yarn discharge spinning fails, since the fiber
bundle is continuously fed from the draft device
10 towards the pneumatic spinning device, the fiber bundle
may accumulate in the vicinity of the inlet of the
pneumatic spinning device. The driven roller is
prevented from being damaged by having the moving
section move the first driven roller to the separated
15 position when the yarn discharge spinning fails.
The pneumatic spinning device may be adapted to
stop the production of the yarn, and the moving section
may be adapted to move the first driven roller from the
contacting position to the separated position when the
20 detecting device does not detect the yarn during the
production of the yarn in the pneumatic spinning device.
When the detecting device cannot detect the yarn due to
yarn breakage, and the like, the first driven roller is
moved to the separated position. Depending on the
25 situation of the yarn breakage, the fiber bundle
sometimes accumulates in the vicinity of the inlet of
the pneumatic spinning device. Even in such a case,
the driven roller is prevented from being damaged by
having the moving section move the first driven roller
30 to the separated position.
The detecting device may be adapted to further
40 / 52
detect a presence or an absence of a yarn defect in the
yarn in addition to the presence or the absence of the
yarn, and the moving section may be adapted to move the
first driven roller from the contacting position to the
5 separated position when the detecting device detects
the yarn defect during production of the yarn in the
pneumatic spinning device. When the yarn defect is
detected, a defective portion of the yarn is removed,
and thereafter, the yarn joining operation is carried
10 out by the yarn joining device. The fiber bundle fed
from the draft device when the yarn is cut or
immediately after the yarn is cut due to the detection
of the yarn defect may accumulate in the vicinity of
the inlet of the pneumatic spinning device. Even in
15 such a case, the air-jet spinning machine can prevent
the driven roller from being damaged by moving the
first driven roller to the separated position.
The moving section may be adapted to move the
first driven roller to the separated position under a
20 state in which the first driven roller is rotating. In
other words, the moving section rapidly moves the first
driven roller to the separated position before the
supply of fiber bundle to the pneumatic spinning device
completely stops. Thus, the air-jet spinning machine
25 can prevent the driven roller from being damaged by the
accumulation of the fiber bundle even when the draft
device is feeding the fiber bundle to the pneumatic
spinning device at high speed.
The moving section may include a first pneumatic
30 cylinder configured to be extended and retracted by air
pressure, and may move the first driven roller to the
41 / 52
separated position by the first pneumatic cylinder
being extended or retracted. Generally, the pneumatic
cylinder that is extended or retracted by pressure of
the supplied air can be rapidly extended or retracted
5 by increasing the air pressure. Thus, the moving
section can rapidly move the first driven roller to the
separated position by using the first pneumatic
cylinder.
The moving section may include a lever adapted to
10 move the first driven roller, and may move the first
driven roller to the separated position by the lever
being operated. In such a case, the moving section can
move the first driven roller to the separated position
at, for example, timing desired by an operator
15 operating the lever.
The draft device may further include a pressing
section adapted to press the first driven roller
against the first driving roller. In such a case, the
draft device can have the fiber bundle sandwiched with
20 the first roller pair under a pressed state, and thus
can draft the fiber bundle without slipping at the
first roller pair.
The air-jet spinning machine may further include
a suction device arranged on the moving section and
25 provided with a suction opening arranged facing the
first driven roller. In such a case, the air-jet
spinning machine can suck fibers attached to the first
driven roller and the like with the suction device.
Furthermore, the air-jet spinning machine can move the
30 suction device accompanying the movement of the first
driven roller to the separated position by the moving
42 / 52
section.
The air-jet spinning machine may include a
plurality of spinning units, each spinning unit
including the draft device, the pneumatic spinning
5 device, the withdrawal device, the winding device, and
the detecting device, wherein the yarn joining device
may be provided one for a prescribed number of the
spinning units or each of the plurality of the spinning
units, and the moving section of the draft device
10 provided in the respective spinning units may be
adapted to move the first driven roller to the
separated position independently of one another. In
such a case, the air-jet spinning machine can move the
first driven roller of a desired spinning unit to the
15 separated position without influencing the spinning
operation of the other spinning units. For example, a
replacement work, and the like of the first driven
roller of the desired spinning unit can be carried out
while the spinning operation of the other spinning
20 units is continuing.
In the air-jet spinning machine, each of the
plurality of the spinning units may further include a
suction device arranged on the moving section and
provided with a suction opening arranged facing the
25 first driven roller. In such a case, the air-jet
spinning machine can suck the fibers attached to the
respective first driven roller and the like of the
spinning units with the suction device arranged in each
spinning unit. Furthermore, the air-jet spinning
30 machine can move the suction device accompanying the
movement of the first driven roller to the separated
43 / 52
position by the moving section 100 in each spinning
unit.
Each of the plurality of the draft devices may
further include a pressing section adapted to press the
5 first driven roller towards the first driving roller,
and the respective pressing section provided in the
plurality of the draft devices may be adapted to press
the first driven roller against the first driving
roller independently of one another. In such a case,
10 the draft device can have the fiber bundle sandwiched
with the first roller pair under a pressed state, and
thus can draft the fiber bundle without slipping at the
first roller pair. Furthermore, the air-jet spinning
machine can press the first driven roller of the
15 desired spinning unit against the first driving roller
irrespective of the pressing state of the draft device
of the other spinning units. In other words, even if
the first driven roller in another spinning unit is
located at the separated position, the spinning
20 operation can continue in the desired spinning unit.
The pressing section may include one of a second
pneumatic cylinder configured to be extended and
retracted by air pressure and a spring, and the first
driven roller may be adapted to be pressed against the
25 first driving roller by the second pneumatic cylinder
being extended or retracted, or by an elastic force of
the spring. When the pressing section includes the
second pneumatic cylinder, the pressing section can
easily change the pressure at which the first driven
30 roller is pressed by adjusting the pressure of the air
supplied to the second pneumatic cylinder. When the
44 / 52
pressing section includes the spring, the pressing
section can press the first driven roller against the
first driving roller without receiving supply of air,
and the like.
5 The inlet of the draft device may be located
below the winding device in a height direction. In
such a case, the air-jet spinning machine can wind the
produced yarn while having the fiber bundle and the
yarn travel from the lower side towards the upper side
10 in the height direction of the air-jet spinning machine.
According to the present invention, the driven
roller most downstream of the draft device can be
prevented from being damaged at the interruption of the
spinning operation.

WE CLAIM:
1. An air-jet spinning machine comprising:
a draft device including a first roller pair and
a second roller pair and adapted to draft a fiber
bundle;
a pneumatic spinning device adapted to produce a
yarn by applying twists to the fiber bundle, fed from
the first roller pair, by a whirling flow of air;
a withdrawal device adapted to withdraw the yarn
from the pneumatic spinning device;
a winding device adapted to wind the yarn
withdrawn by the withdrawal device;
a detecting device (8; 9; 36; 38; 39; 51) adapted
to detect a presence or an absence of the yarn; and
a yarn joining device adapted to join the yarn
produced by the pneumatic spinning device and the yarn
wound by the winding device,
wherein the first roller pair includes a first
driving roller (17a) and a first driven roller (17b);
the second roller pair includes a second driving
roller (18a) and a second driven roller (18b);
the draft device includes:
a moving section (100) adapted to move the
first driven roller (17b) between a contacting position
and a separated position, the contacting position being
a position where the first driven roller (17b) makes
contact with the first driving roller (17a) and the
separated position being a position where the first
driven roller (17b) is located away from the first
driving roller (17a) and an inlet of the pneumatic
spinning device, and
a draft cradle adapted to cause the second
driven roller (18b) to make contact with the second
driving roller (18a); and
the moving section (100) is adapted to move the
first driven roller (17b) to the separated position and
the draft cradle is adapted to maintain the second
driven roller (18b) in contact with the second driving
roller (18a), at an interruption of an spinning
operation of the yarn.
2. The air-jet spinning machine as claimed in
claim 1, wherein the pneumatic spinning device
includes:
a fiber guiding section adapted to guide the
fiber bundle fed from the draft device;
a nozzle block including a spinning chamber in
which fibers of the fiber bundle guided by the fiber
guiding section are whirled by the whirling flow, and a
first nozzle through which air for generating the
whirling flow passes; and
a hollow guide shaft body including a passage
adapted to guide the fibers whirled in the spinning
chamber to outside, and a second nozzle through which
air to be injected into the passage passes,
wherein during yarn discharge spinning in which
production of the yarn is started from a state in which
the fiber bundle is not fed from the draft device, the
air is injected from at least the second nozzle, and
the fiber bundle drafted by the draft device is fed
into the spinning chamber from the fiber guiding
section.
3. The air-jet spinning machine as claimed in
claim 2, wherein the moving section (100) is adapted to
move the first driven roller (17b) from the contacting
position to the separated position when the detecting
device (8; 9; 36; 38; 39; 51) does not detect the yarn
within a prescribed period of time from a start of the
yarn discharge spinning.
4. The air-jet spinning machine as claimed in
any one of claims 1 to 3, wherein the pneumatic
spinning device is adapted to stop production of the
yarn and the moving section (100) is adapted to move
the first driven roller (17b) from the contacting
position to the separated position when the detecting
device (8; 9; 36; 38; 39; 51) does not detect the yarn
during production of the yarn by the pneumatic spinning
device.
5. The air-jet spinning machine as claimed in
any one of claims 1 to 4, wherein the detecting device
(8; 9) is adapted to further detect a presence or an
absence of a yarn defect in the yarn in addition to the
presence or the absence of the yarn, and
the moving section (100) is adapted to move the
first driven roller (17b) from the contacting position
to the separated position when the detecting device (8;
9) detects the yarn defect during production of the
yarn by the pneumatic spinning device.
6. The air-jet spinning machine as claimed in
any one of claims 1 to 5, wherein the moving section
(100) is adapted to move the first driven roller (17b)
to the separated position under a state in which the
first driven roller (17b) is rotating.
7. The air-jet spinning machine as claimed in
any one of claims 1 to 6, wherein the moving section
(100) includes a first pneumatic cylinder (101)
configured to be extended and retracted by air pressure,
and the first driven roller (17b) is moved to the
separated position by the first pneumatic cylinder
(101) being extended or retracted.
8. The air-jet spinning machine as claimed in
any one of claims 1 to 7, wherein the moving section
(100) includes a lever adapted to move the first driven
roller (17b), and the first driven roller (17b) is
moved to the separated position by the lever being
operated.
9. The air-jet spinning machine as claimed in
any one of claims 1 to 8, wherein the draft device
includes a pressing section (100) adapted to press the
first driven roller (17b) against the first driving
roller (17a).
10. The air-jet spinning machine as claimed in
any one of claims 1 to 9, comprising a suction device
(110) arranged on the moving section (100) and provided
with a suction opening (112a) arranged facing the first
driven roller (17b).
11. The air-jet spinning machine as claimed in
any one of claims 1 to 8, comprising a plurality of
spinning units, each spinning unit including the draft
device, the pneumatic spinning device, the withdrawal
device, the winding device, and the detecting device
(8; 9; 36; 38; 39; 5 1 ),
wherein the yarn joining device is provided for a
predetermined number of the spinning units or for each
of the plurality of the spinning units, and
the moving sections (100) of the draft device
provided in the respective spinning units are adapted
to move the first driven roller (17b) to the separated
position independently of one another.
12. The air-jet spinning machine as claimed in
claim 11, wherein each of the plurality of the spinning
units includes a suction device (110) arranged on the
moving section (100) and provided with a suction
opening (112a) arranged facing the first driven roller
(17b).
13. The air-jet spinning machine as claimed in
claim 11 or 12, wherein each of the plurality of the
draft device includes a pressing section (100) adapted
to press the first driven roller (17b) towards the
first driving roller (17a), and
the respective pressing section (100) provided in
the plurality of the draft devices is adapted to press
the first driven roller (17b) against the first driving
roller (17a) independently of one another.
14. The air-jet spinning machine as claimed in
claim 9 or 13, wherein the pressing section (100)
includes one of a second pneumatic cylinder (101)
configured to be extended and retracted by air pressure
and a spring, and
the first driven roller (17b) is adapted to be
pressed against the first driving roller (17a) by the
second pneumatic cylinder (101) being extended or
retracted, or by an elastic force of the spring.
15. The air-jet spinning machine as claimed in
any one of claims 1 to 14, wherein an inlet of the
draft device is located lower than the winding device in a height direction.