PNEUMATIC SPINNING MACHINE
BACKGROUND OF THE INVENTION
5 1. Field of the Invention
The present invention relates to a pneumatic
spinning device and a pneumatic spinning machine
including the same.
2. Description of the Related Art
10 Conventionally, there is known a pneumatic
spinning device that twists fibers by the action of
whirling airflow formed in a spinning chamber and forms
a spun yarn. Japanese Patent Laid-Open No. 2003-268636
(Patent Document 1) discloses a device for producing a
15 spun yarn from a staple fiber bundle as this type of
pneumatic spinning device. Japanese Unexamined Patent
Publication No. 2004-509243 (Patent Document 2)
discloses a device that produces a spun yarn from a fiber
sliver as this type of pneumatic spinning device.
20 The device of Patent Document 1 includes a fiber
guide element having a fiber-guiding surface and a
spindle having a yarn guide passage. The fiber-guiding
surface includes a direction-changing position. The
direction-changing position causes the directional
25 change of the staple fiber bundle when the staple fiber
bundle is guided by the fiber-guiding surface. The
fiber-guiding surface ends at a fiber passing edge. The
spindle is arranged downstream of this fiber passing
edge. The yarn guide passage of the spindle has an inlet
30 opening facing the fiber passing edge. A fluid device
for forming a swirl flow around the inlet opening is
3
provided between the fiber guide element and the inlet
opening. With this configuration, when the fluidic
device generates a swirl flow around the inlet opening
or the spindle, the generated swirl flow can cause a
5 free fiber end of the staple fiber bundle to be
positioned around the inlet opening. The free fiber end
performs a relative rotation motion about the inlet
opening and thus the staple fiber bundle. Accordingly,
the device forms a spun yarn from the staple fiber bundle.
10 The device of Patent Document 2 includes a fiber
conveyance element having a fiber-guiding surface and a
spindle having a yarn guide channel. A fiber outlet
edge is arranged at an end of the fiber-guiding surface
in the conveyance direction. An intake port of the yarn
15 guide channel is arranged in close proximity to the fiber
outlet edge. Patent Document 2 describes that a set
distance between an imaginary plane parallel to a center
line of the yarn guide channel including the fiber outlet
edge and the center line is preferably a value within
20 the order range of 10 to 30% of the diameter of the
intake port. With this configuration, the device guides
the fibers to the fiber-guiding surface and, from there,
into the intake port of the yarn guide channel. Then,
the device generates a vortex airflow around the intake
25 port of the yarn guide channel, and causes the vortex
airflow to swirl a free rear end of the fibers whose
front end is already positioned in the yarn guide channel,
thereby producing a yarn.
30 BRIEF SUMMARY OF THE INVENTION
A fiber bundle used as a raw material for spun yarn
4
is composed of a multitude of fibers. When the fiber
bundle is introduced into the spinning chamber for
pneumatic spinning, focusing on each fiber, a downstream
end positioned downstream in the travelling direction of
5 the fiber is twisted into a twisted core portion (twisted
by swirling of the reversal portion described later),
and provided as a fixed end. On the other hand, an
upstream end positioned upstream of the fibers in the
travelling direction is a free end, and the upstream end
10 separates so as to open from the core portion when
entering the spinning chamber and reverses the direction
of the end. This reversal portion is subjected to action
of the whirling airflow, whereby each fiber is wound
around the core portion. In this manner, pneumatic
15 spinning is performed.
The pneumatic spinning device is desired to
increase spinning speed. With an increase in spinning
speed, the time in which the fiber bundle is subjected
to the action of the whirling airflow in the spinning
20 chamber becomes shorter. Therefore, in order to realize
high-speed spinning while sufficiently twisting the
fibers, it is necessary to reliably reverse the free end
portion of the fibers in the spinning chamber (in other
words, increase the amount of the fibers to be reversed).
25 On the other hand, when the amount of the reversed fibers
increases, the twist tends to propagate from the reversed
fibers to the fibers upstream of the reversed fibers in
the travelling direction. The fibers in which the twist
has propagated are not sufficiently reversed even if
30 subjected to the action of the whirling airflow.
Therefore, it has been difficult to perform stable
5
spinning at high speed.
In the configuration of Patent Document 1, in case
the spinning speed is high, when the swirl flow causes
the free fiber end to perform relative rotation motion,
5 the twist propagates to the staple fiber bundle
positioned on the fiber-guiding surface side, whereby
the relative rotation motion of the free fiber end is
highly likely to become unstable.
In Patent Document 2, in case the spinning speed
10 is high, when the vortex airflow causes the free rear
end of the fibers to rotate, the twist propagates to the
fibers on the fiber-guiding surface side, whereby the
rotation of the free rear end of the fibers is highly
likely to become unstable. Patent Document 2 discloses
15 that direction-changing and guiding of the fibers along
the fiber outlet edge prevents twist propagation, but
the effect is unknown for spinning at high speed.
An object of the present invention lies in that in
a pneumatic spinning device, when fibers are twisted by
20 whirling airflow, propagation of the twist to the fibers
positioned upstream of the twisted fibers in the
travelling direction is effectively reduced.
A pneumatic spinning device that forms a yarn by
twisting, by whirling airflow, fibers passing through a
25 spinning chamber, the pneumatic spinning device
comprises a fiber guiding section having a first passage
through which a fiber bundle passes; and a hollow guide
shaft body that has a second passage through which the
fiber bundle having passed through the first passage is
30 guided, and that is provided so as to face the fiber
guiding section across the spinning chamber, wherein the
6
first passage is provided so as to extend linearly, the
second passage is provided so as to extend along a shaft
center of the hollow guide shaft body with the shaft
center as a center, a downstream end where the first
5 passage opens into the spinning chamber and an upstream
end where the second passage opens into the spinning
chamber are arranged with an interval in a direction of
the shaft center of the hollow guide shaft body, an inner
surface of the first passage has a flat plane portion on
10 a side close to the shaft center of the hollow guide
shaft body, an angle of a linear portion obtained by
cutting the plane portion with any plane perpendicular
to a first direction in which the first passage extends
with respect to the first direction is constant between
15 an upstream end and the downstream end of the first
passage, the plane portion is arranged to deviate with
respect to the shaft center of the hollow guide shaft
body in a second direction perpendicular to a direction
of the shaft center of the hollow guide shaft body, and
20 an interval in the second direction between a downstream
end of the plane portion and the shaft center of the
hollow guide shaft body is equal to or greater than 0.8
mm and equal to or less than 3.4 mm.
A pneumatic spinning machine including the
25 pneumatic spinning device, the pneumatic spinning
machine comprises a first catching device adapted to
catch a yarn formed by the pneumatic spinning device at
a time of yarn discharge spinning; a winding device
adapted to wind a yarn formed by the pneumatic spinning
30 device; a second catching device adapted to catch a wound
yarn; and a yarn joining device adapted to join the yarn
7
caught by the first catching device and the yarn caught
by the second catching device.
BRIEF DESCRIPTION OF THE DRAWINGS
5 FIG. 1 is a front view illustrating the overall
configuration of a pneumatic spinning machine including
a pneumatic spinning device according to an embodiment
of the present invention;
FIG. 2 is a side view of a spinning unit and a yarn
10 joining cart;
FIG. 3 is a partial cross-sectional view
illustrating a configuration of the spinning device;
FIG. 4 is a partially enlarged view of FIG. 3;
FIG. 5 is a perspective view illustrating a
15 positional relationship between a first passage and a
second passage formed in the spinning device;
FIGS. 6A and 6B are views illustrating a crosssectional shape of the first passage;
FIGS. 7A and 7B are views illustrating another
20 example of the cross-sectional shape of the first
passage;
FIG. 8 is a partial cross-sectional view
illustrating another example of the configuration of the
pneumatic spinning device; and
25 FIG. 9 is a partial cross-sectional view
illustrating another example of the configuration of the
pneumatic spinning device.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
30 Next, a pneumatic spinning machine 1 including a
pneumatic spinning device 23 according to an embodiment
8
of the present invention will be described with reference
to FIGS. 1 and 2.
As illustrated in FIG. 1, the pneumatic spinning
machine 1 includes a blower box 3, a motor box 5, a
5 plurality of spinning units 7, and a yarn joining cart
9. The plurality of spinning units 7 are arranged in a
predetermined direction.
In the blower box 3, a blower 11 that functions as
a negative pressure source is arranged.
10 In the motor box 5,a drive source (not illustrated),
a central control section 13, a display section 15, and
an operation section 17 are arranged. The drive source
provided in the motor box 5 includes a motor commonly
used by the plurality of spinning units 7.
15 The central control section 13 intensively manages
and controls each section of the pneumatic spinning
machine 1. As illustrated in FIG. 2, the central control
section 13 is connected via a signal line not illustrated
to a unit control section 19 included in each spinning
20 unit 7. While in the present embodiment, each spinning
unit 7 includes the unit control section 19, a
predetermined number (e.g., two or four) of spinning
units 7 may share one unit control section 19.
The display section 15 can display, for example,
25 setting contents for the spinning units 7 and/or
information regarding the state of each spinning unit 7.
When the display section 15 is constituted with a touchscreen display, the display section 15 and the operation
section 17 may be integrally configured.
30 Each spinning unit 7 mainly includes a draft device
21, the pneumatic spinning device 23, a yarn accumulating
9
device 25, and a winding device 27 arranged in order
from upstream to downstream. The “upstream” and
“downstream” here mean upstream and downstream in the
travelling direction of a sliver 32, a fiber bundle 34,
5 and a spun yarn 30 at the time of winding of the spun
yarn (yarn) 30.
The draft device 21 is provided in a vicinity of
an upper end of a frame 36 included in the pneumatic
spinning machine 1. As illustrated in FIG. 2, the draft
10 device 21 includes four draft roller pairs. The four
draft roller pairs are a back roller pair 41, a third
roller pair 43, a middle roller pair 45, and a front
roller pair 47, which are arranged in order from upstream
to downstream. The middle roller pair 45 is provided
15 with an apron belt 49 for each roller.
By sandwiching and conveying the sliver 32 supplied
from a sliver case not illustrated between rollers of
each draft roller pair, the draft device 21 stretches
(drafts) the sliver 32 to a predetermined fiber amount
20 (or thickness) to form the fiber bundle 34. The fiber
bundle 34 formed by the draft device 21 is supplied to
the pneumatic spinning device 23.
By applying whirling airflow to the fiber bundle
34 formed by the draft device 21, the pneumatic spinning
25 device 23 twists the fiber bundle 34 to form the spun
yarn 30. The detailed configuration of the pneumatic
spinning device 23 will be described later.
The yarn accumulating device 25 is supplied with
the spun yarn 30 formed by the pneumatic spinning device
30 23. As illustrated in FIG. 2, the yarn accumulating
device 25 includes a yarn accumulating roller 53 and a
10
motor 55.
The yarn accumulating roller 53 is rotationally
driven by the motor 55. The yarn accumulating roller 53
winds the spun yarn 30 around its outer peripheral
5 surface and temporarily accumulates the spun yarn 30.
By rotating at a predetermined rotation speed with the
spun yarn 30 wound around the outer peripheral surface
thereof, the yarn accumulating roller 53 pulls out the
spun yarn 30 from the pneumatic spinning device 23 at a
10 predetermined speed and conveys it to the downstream.
As described above, the yarn accumulating device
25 can temporarily accumulate the spun yarn 30 on the
outer peripheral surface of the yarn accumulating roller
53, and hence functions as a kind of buffer for the spun
15 yarn 30. Accordingly, it is possible to eliminate a
defect (such as slackening of the spun yarn 30) caused
by difference between the spinning speed in the pneumatic
spinning device 23 and the winding speed (travel speed
of the spun yarn 30 to be wound on a package 73 described
20 later) for some reason.
A yarn monitoring device 59 is provided between
the pneumatic spinning device 23 and the yarn
accumulating device 25. The spun yarn 30 formed by the
pneumatic spinning device 23 passes through the yarn
25 monitoring device 59 before being accumulated in the
yarn accumulating device 25.
The yarn monitoring device 59 monitors the quality
of the traveling spun yarn 30 by an optical sensor and
detects a yarn defect included in the spun yarn 30. The
30 yarn defect can be, for example, an abnormality in the
thickness of the spun yarn 30 or a foreign substance
11
contained in the spun yarn 30. When detecting a yarn
defect in the spun yarn 30, the yarn monitoring device
59 transmits a yarn defect detection signal to the unit
control section 19. The yarn monitoring device 59 may
5 monitor the quality of the spun yarn 30 by using, for
example, a capacitance sensor instead of the optical
sensor. Instead of these examples, or in addition to
these examples, the yarn monitoring device 59 may be
configured to measure tension of the spun yarn 30 as the
10 quality of the spun yarn 30.
Upon receiving the yarn defect detection signal
from the yarn monitoring device 59, the unit control
section 19 cuts the spun yarn 30 by stopping the driving
of the pneumatic spinning device 23 and/or the draft
15 device 21. That is, the pneumatic spinning device 23
functions as a cutting section that cuts the spun yarn
30 when the yarn monitoring device 59 detects a yarn
defect. The spinning unit 7 may be provided with a
cutter for cutting the spun yarn 30.
20 The winding device 27 includes a cradle arm 61, a
winding drum 63, and a traverse guide 65. The cradle
arm 61 is swingably supported about a supporting shaft
67 and can rotatably support a bobbin 71 (that is, the
package 73) for winding the spun yarn 30. By rotating
25 in a state of being in contact with the outer peripheral
surface of the bobbin 71 or the package 73, the winding
drum 63 rotationally drives the package 73 in the winding
direction. While reciprocating the traverse guide 65 by
a driving means not illustrated, the winding device 27
30 drives the winding drum 63 by an electric motor not
illustrated. Accordingly, the winding device 27 winds
12
the spun yarn 30 around the package 73 while traversing
the spun yarn 30.
As illustrated in FIG. 1, on the frame 36 of the
pneumatic spinning machine 1, a rail 81 is arranged along
5 a direction in which the plurality of spinning units 7
are arranged. The yarn joining cart 9 is configured to
be capable of traveling on the rail 81. Accordingly,
the yarn joining cart 9 can move with respect to the
plurality of spinning units 7. The yarn joining cart 9
10 travels to the spinning unit 7 where yarn breakage or
yarn cutting has occurred, and performs yarn joining
work for the spinning unit 7.
As illustrated in FIG. 1, the yarn joining cart 9
includes travel wheels 83, a yarn joining device 85, a
15 suction pipe (first catching device) 87, and a suction
mouth (second catching device) 89. The yarn joining
cart 9 further includes a cart control section 91
illustrated in FIG. 2.
The suction pipe 87 can catch the spun yarn 30
20 formed by the pneumatic spinning device 23 at the time
of yarn discharge spinning. Specifically, by generating
a suction airflow at the tip of the suction pipe 87, the
suction pipe 87 can suck and catch the spun yarn 30
discharged from the pneumatic spinning device 23.
25 The suction mouth 89 can catch the spun yarn 30
wound around the package 73 of the winding device 27.
Specifically, by generating a suction airflow at the tip
of the suction mouth 89, the suction mouth 89 can suck
and catch the spun yarn 30 from the package 73 supported
30 by the winding device 27.
By swinging in a state in which the spun yarn 30
13
is caught, for example, the suction pipe 87 and the
suction mouth 89 guide the spun yarn 30 to a position
where the spun yarn 30 can be introduced into the yarn
joining device 85.
5 The yarn joining device 85 joins the spun yarn 30
from the pneumatic spinning device 23 and the spun yarn
30 from the package 73. In the present embodiment, the
yarn joining device 85 is a splicer device that twists
yarn ends together by whirling airflow. The yarn joining
10 device 85 is not limited to the splicer device described
above, and for example, a mechanical knotter and the
like can be adopted.
The cart control section 91 (see FIG. 2) is
configured as a known computer having a central
15 processing unit (CPU), a read only memory (ROM), a random
access memory (RAM), and the like that are not
illustrated. By controlling the operation of each
section included in the yarn joining cart 9, the cart
control section 91 controls the yarn joining work
20 performed by the yarn joining cart 9.
The configuration of the pneumatic spinning device
23 will be described in detail with reference to FIG. 3.
As illustrated in FIG. 3, the pneumatic spinning
device 23 includes a fiber guide (fiber guiding section)
25 101, a spindle (hollow guide shaft body) 102, and a
nozzle block (casing) 103.
A fiber guide 101 has a first passage 111 through
which the fiber bundle 34 can pass. The first passage
111 is connected to a spinning chamber 113 for performing
30 pneumatic spinning. The fiber guide 101 is supplied
with the fiber bundle 34 formed by the draft device 21.
14
The fiber bundle 34 is introduced into the first passage
111 of the fiber guide 101 from its upstream end 111a,
and is guided to the spinning chamber 113 through a
downstream end 111b.
5 The fiber guide 101 includes a body 115 formed in
a block shape. The body 115 is arranged such that its
upstream end surface 115a faces the draft device 21 and
its downstream end surface 115b faces the spindle 102.
The first passage 111 is composed of a hole 117 formed
10 so as to penetrate the body 115. The hole 117 is
arranged so as to extend linearly from the upstream end
surface 115a to the downstream end surface 115b of the
body 115. Hereinafter, the direction in which the first
passage 111 extends may be referred to as the first
15 direction. In the present embodiment, the first
direction is parallel to a shaft center 108 of the
spindle 102 described below.
The fiber guide 101 constitutes a part of the
spinning chamber 113. Specifically, the spinning
20 chamber 113 is formed by arranging the downstream end
surface 115b of the body 115 to face an internal space
of the nozzle block 103 described later.
The spindle 102 is arranged downstream with respect
to the fiber guide 101. The spindle 102 is formed in an
25 elongated round bar shape along the travelling direction
of the fiber bundle 34. The spindle 102 is arranged
such that its upstream end surface 102a faces the fiber
guide 101 across the spinning chamber 113.
The spindle 102 has a second passage 122 through
30 which the fiber bundle 34 having passed through the first
passage 111 is guided. The second passage 122 is
15
connected to the spinning chamber 113. The second
passage 122 is composed of a circular hole 126 formed in
the spindle 102. The second passage 122 extends linearly
inside the spindle 102 along the longitudinal direction
5 of the spindle 102. An upstream end 122a of the second
passage 122 opens into the upstream end surface 102a of
the spindle 102. The center of the second passage 122
coincides with the shaft center 108 of the spindle 102.
A conical taper portion 124 is formed on the outer
10 peripheral surface of the upstream end of the spindle
102. The taper portion 124 is provided so that the outer
diameter becomes smaller from the downstream to the
upstream.
The spindle 102 constitutes a part of the spinning
15 chamber 113. Specifically, the spinning chamber 113 is
formed by arranging the outer peripheral surface of the
taper portion 124 in the internal space of the nozzle
block 103. The upstream end surface 102a of the spindle
102 is arranged at an appropriate interval with respect
20 to the body 115 of the fiber guide 101.
The spinning chamber 113 is composed of a space
surrounded by the downstream end surface 115b of the
body 115 of the fiber guide 101, the outer peripheral
surface of the taper portion 124 of the spindle 102, and
25 an inner surface 103a of the nozzle block 103 described
later.
The upstream end 122a of the second passage 122 is
arranged at an appropriate interval with respect to the
downstream end 111b of the first passage 111 in the
30 travelling direction of the fiber bundle 34. The
spinning chamber 113 described above is configured to
16
include a portion with this interval.
The downstream end 111b of the first passage 111
and the upstream end 122a of the second passage 122 open
into the spinning chamber 113. In the present embodiment,
5 the opening surface of the downstream end 111b of the
first passage 111 and the opening surface of the upstream
end 122a of the second passage 122 are substantially
parallel. In the body 115, the surface (downstream end
surface 115b) at which the downstream end 111b of the
10 first passage 111 opens is a flat surface facing the
spinning chamber 113 and is perpendicular to the shaft
center 108 of the spindle 102.
The opening area of the downstream end 111b of the
first passage 111 is substantially the same as or the
15 same as a passage area of the first passage 111. The
passage area refers to an area of a cross section of the
passage cut with a plane perpendicular to the
longitudinal direction. The opening area of the
upstream end 122a of the second passage 122 is
20 substantially the same as or the same as a passage area
of a portion of the second passage 122 corresponding to
the taper portion 124.
After coming out from the downstream end 111b of
the first passage 111, the fiber bundle 34 enters the
25 upstream end 122a of the second passage 122 via the
spinning chamber 113. The fiber bundle 34 passes through
the second passage 122 and is sent out to the outside of
the pneumatic spinning device 23.
The nozzle block 103 is arranged downstream of the
30 fiber guide 101. The nozzle block 103 is arranged so as
to cover the spindle 102. Between the nozzle block 103
17
and the spindle 102, a gap is formed in the radial
direction of the spindle 102.
A circular hole is formed in the nozzle block 103.
A shaft center of the circular hole coincides with the
5 shaft center 108 of the spindle 102. The inner surface
103a of the nozzle block 103 is formed to have a circular
shape when viewed in the direction of the shaft center
108 of the spindle 102.
The nozzle block 103 has the spinning nozzle 131
10 through which air can pass. The pneumatic spinning
device 23 can eject air (compressed air) from the
spinning nozzle 131 into the spinning chamber 113. The
spinning nozzle 131 is formed as a through hole extending
in a direction inclined with respect to the shaft center
15 108 of the spindle 102. One longitudinal end of the
spinning nozzle 131 is connected to a compressed air
supplying section not illustrated, and the other
longitudinal end opens into the spinning chamber 113.
When compressed air is jetted from the spinning nozzle
20 131 into the spinning chamber 113, whirling airflow is
generated in the spinning chamber 113.
In the present embodiment, a plurality of the
spinning nozzles 131 are formed in the nozzle block 103.
The plurality of spinning nozzles 131 are arranged at
25 equal intervals in the circumferential direction.
However, the number of the spinning nozzles 131 is not
limited, and it is sufficient that one or more spinning
nozzles 131 are arranged.
The spindle 102 has an auxiliary nozzle (passage
30 hole) 135 through which air can pass. The pneumatic
spinning device 23 can eject air (compressed air) from
18
the auxiliary nozzle 135 to the second passage 122. The
auxiliary nozzle 135 is formed as a through hole
extending in a direction perpendicular to the shaft
center 108 of the spindle 102. One longitudinal end of
5 the auxiliary nozzle 135 is connected to the compressed
air supplying section not illustrated, and the other
longitudinal end opens into the second passage 122.
A plurality of the auxiliary nozzles 135 are
provided around the second passage 122. The plurality
10 of auxiliary nozzles 135 are arranged at equal intervals
in the circumferential direction.
When compressed air is jetted from the auxiliary
nozzle 135 to the second passage 122, whirling airflow
is generated in the second passage 122. When viewed in
15 a direction along the shaft center 108 of the spindle
102, the direction of this whirling airflow is opposite
to the direction of the whirling airflow generated by
the jetting of compressed air from the spinning nozzle
131.
20 The pneumatic spinning device 23 can perform two
types of spinning, one is normal spinning and the other
is yarn discharge spinning. The normal spinning is
spinning performed while winding the spun yarn 30
downstream of the pneumatic spinning device 23. The
25 yarn discharge spinning is a temporary spinning
performed at the stage before the normal spinning, and
is started in a state where the spun yarn 30 is not
discharged to the downstream of the pneumatic spinning
device 23. The yarn discharge spinning is sometimes
30 called self-spinning because the pneumatic spinning
device 23 performs spinning only by applying whirling
19
airflow.
When the pneumatic spinning device 23 performs yarn
discharge spinning, compressed air is jetted from the
auxiliary nozzle 135 before the spinning nozzle 131.
5 Since the second passage 122 is formed so that the
passage area increases towards downstream, the whirling
airflow flowing downstream is formed in the second
passage 122 by the jetting of the compressed air from
the auxiliary nozzle 135. When the fiber bundle 34 is
10 supplied from the draft device 21 to the pneumatic
spinning device 23 in this state, the fiber bundle 34 is
guided from the first passage 111 through the spinning
chamber 113 to the second passage 122. Due to the action
of the whirling airflow formed by the jetting of the
15 compressed air from the auxiliary nozzle 135, a portion
of the fiber bundle 34 passing through the second passage
122 is twisted for some extent.
Subsequently, the compressed air is jetted from
the spinning nozzle 131, and whirling airflow is formed
20 in the spinning chamber 113. This whirling airflow acts
on a portion of the fiber bundle 34 passing through the
spinning chamber 113.
Hereinafter, the behavior of the fibers will be
described by focusing on the portion of the fiber bundle
25 34 passing through the spinning chamber 113. The
downstream end of the fibers in the travelling direction
constituting such portion of the fiber bundle 34 is
twisted into and fixed to the core portion of the fiber
bundle 34 inside the second passage 122. On the other
30 hand, since the upstream end in the travelling direction
is not twisted, this free end is separated so as to open
20
from the core portion by the whirling airflow in the
spinning chamber 113, and swirls in the state where the
direction is reversed along the outer peripheral surface
of the taper portion 124. Accordingly, the fibers wind
5 around the core portion, and the fiber bundle 34 is
twisted. The spun yarn 30 thus formed travels downstream
by the whirling airflow formed by the compressed air
jetted from the auxiliary nozzle 135, and is discharged
from the pneumatic spinning device 23.
10 In the normal spinning, the jetting of air from
the auxiliary nozzle 135 is not performed. In the normal
spinning, the spun yarn 30 is wound downstream of the
pneumatic spinning device 23, thereby realizing travel
of the spun yarn 30 in the pneumatic spinning device 23.
15 The principle of the normal spinning is basically the
same as that of the yarn discharge spinning, and the
fiber bundle 34 is twisted by applying the whirling
airflow formed by the spinning nozzle 131.
Next, the configuration of the pneumatic spinning
20 device 23 will be described in more detail with reference
to FIGS. 4 and 5 and the like.
As illustrated in FIGS. 4 and 5, in the fiber guide
101, a plane portion 151 is formed on a part of the inner
surface of the first passage 111. In FIG. 5, the plane
25 portion 151 is illustrated by being emphasized by
hatching. Among the inner surface of the first passage
111, the plane portion 151 is arranged on a side closer
to the shaft center 108 of the spindle 102.
The plane portion 151 is arranged along the first
30 direction from the upstream end 111a to the downstream
end 111b of the first passage 111. A downstream end
21
151a of the plane portion 151 constitutes a part of the
contour of the opening formed in the spinning chamber
113 by the first passage 111.
The plane portion 151 has a flat shape without
5 twist. In other words, the angle of the linear portion
obtained by cutting the plane portion 151 with any plane
perpendicular to the first direction with respect to the
first direction is constant from the upstream end to the
downstream end 151a of the plane portion 151.
10 The plane portion 151 is arranged to deviate (to
be displaced) with respect to the shaft center 108 of
the spindle 102 in the direction perpendicular to the
direction of the shaft center 108 of the spindle 102.
Hereinafter, the direction perpendicular to the
15 direction of the shaft center 108 of the spindle 102 may
be referred to as the second direction.
Regarding the size of the above deviation, an
interval S1 in the second direction between the
downstream end 151a of the plane portion 151 and a center
20 122b of the upstream end 122a of the second passage 122,
i.e., interval S1 in the second direction between the
downstream end 151a of the plane portion 151 and the
shaft center 108 of the spindle 102 is equal to or
greater than 0.8 mm and equal to or less than 3.4 mm.
25 In the pneumatic spinning device 23 of the present
embodiment, a known needle-shaped member is not arranged
in the spinning chamber 113.
As a result of an experiment using the pneumatic
spinning device 23, as long as the above-mentioned
30 interval S1 is equal to or greater than 0.8 mm and equal
to or less than 3.4 mm, the pneumatic spinning device 23
22
was able to continuously form the spun yarn 30 even if
the pneumatic spinning device 23 does not include a known
needle-shaped member when spinning is performed at a
high spinning speed such as 400 m/min, or even 450 m/min
5 for example. On the other hand, when the interval S1
was less than 0.8 mm, the pneumatic spinning device 23
was not able to stably form the spun yarn 30 continuously.
When the interval S1 was greater than 3.4 mm, the
pneumatic spinning device 23 was not able to perform
10 spinning.
Therefore, when the above-mentioned interval S1 is
equal to or greater than 0.8 mm and equal to or less
than 3.4 mm, the pneumatic spinning device 23 can perform
yarn discharge spinning. On the other hand, when the
15 interval S1 is less than 0.8 mm or more than 3.4 mm, the
pneumatic spinning device 23 is not able to perform yarn
discharge spinning.
The interval S1 is magnitude (length) of the
distance in which the plane portion 151 is arranged to
20 deviate with respect to the shaft center 108 of the
spindle 102. If the interval S1 is too small, bending
of a travelling path of the fiber bundle 34 becomes loose,
and hence the force with which the fiber bundle 34 is
pressed against the plane portion 151 upstream of the
25 spinning chamber 113 becomes weak. As a result, the
restraint of the fiber bundle 34 becomes insufficient,
and the twist of the fiber bundle 34 in the spinning
chamber 113 propagates to the fiber bundle 34 located in
the first passage 111. The fibers of the fiber bundle
30 34 having been weakly twisted by the propagation of the
twist from downstream is not sufficiently separated and
23
reversed even if subjected to the action of the whirling
airflow in the spinning chamber 113 after passing through
the first passage 111. Therefore, it is difficult to
apply twists to the fiber bundle 34 well. On the other
5 hand, if the interval S1 is too large, the inclination
of the path of the fiber bundle 34 in the spinning
chamber 113 becomes too much, and it is sometimes
difficult to apply well the whirling airflow to the fiber
bundle 34. Accordingly, setting the interval S1 within
10 the above range is preferable.
The interval S1 can be set arbitrarily as long as
it is equal to or greater than 0.8 mm and equal to or
less than 3.4 mm. However, in consideration of stably
performing high-speed spinning, the interval S1 is
15 preferably equal to or greater than 0.9 mm and equal to
or less than 1.5 mm, and more preferably 1 mm.
The plane portion 151 is arranged at a position
where the plane portion 151 and the opening formed by
the second passage 122 in the spinning chamber 113 do
20 not appear to overlap each other when viewed in the first
direction. As illustrated in FIG. 4, the plane portion
151 is arranged outside with respect to an edge of the
second passage 122 (on the side far from the shaft center
108 of the spindle 102). However, the plane portion 151
25 may be arranged at a position where the plane portion
151 and the second passage 122 appear to overlap each
other when viewed in the first direction.
In the present embodiment, as illustrated in FIG.
6A, the cross-sectional shape of the first passage 111
30 when the fiber guide 101 is cut with a plane
perpendicular to the first direction is a quadrangle
24
having a linear portion corresponding to the plane
portion 151 as one side. Specifically, the quadrangle
of the cross-sectional shape is an elongated rectangle,
and all four corners are rounded in an arc shape. The
5 linear portion described above corresponds to one of the
long sides of the rectangle. When considering a line
segment connecting a point bisecting the linear portion
and the shaft center 108 of the spindle 102, this line
segment and the linear portion are perpendicular.
10 The cross-sectional shape is line symmetric with
respect to the above line segment. Therefore, in the
cross-sectional shape, in the direction orthogonal to
the linear portion corresponding to the plane portion
151, provided that the distance between the linear
15 portion and the contour on the opposite side of the
linear portion across the first passage 111 is called a
gap length G, the gap length G is constant over the
entire longitudinal direction of the linear portion (G1
= G2 = G3).
20 As an alternative embodiment, as illustrated in
FIG. 6B, the cross-sectional shape may be a D shape
formed by a linear portion formed by the plane portion
151 and an arcuate portion continuous with the linear
portion. In this cross-sectional shape, the gap length
25 G at the longitudinal center of the linear portion is
larger than the gap length G at both longitudinal ends
(G1 > G2, G1 > G3).
As illustrated in FIG. 7A, the cross-sectional
shape of the first passage 111 may be a quadrangle
30 without rounded corners. As illustrated in FIG. 7B, the
cross-sectional shape of the first passage 111 may be a
25
triangle.
In the present embodiment, as illustrated in FIG.
4, a length L1 of the plane portion 151 in the first
direction is equal to or greater than 3 mm and equal to
5 or less than 12 mm.
An inner diameter D1 of the nozzle block 103
(strictly speaking, the inner diameter of the portion of
the nozzle block 103 surrounding the taper portion 124)
is equal to or greater than 3 mm and equal to or less
10 than 9 mm.
In the configurations illustrated in FIGS. 3 to 5,
the plane portion 151 is arranged parallel to the shaft
center 108 of the spindle 102. However, as an
alternative embodiment, as illustrated in FIG. 8, the
15 plane portion 151 may be arranged to be inclined at an
angle θ1 equal to or less than 10° with respect to the
shaft center 108 of the spindle 102. Although FIG. 8
illustrates an example of inclination to one side, the
plane portion 151 may be arranged to be inclined at the
20 angle θ1 equal to or less than 10 degrees towards a side
opposite to the example of FIG. 8.
As an alternative embodiment, as illustrated in
FIG. 9, the downstream end 151a of the plane portion 151
may be arranged upstream relative to the downstream end
25 111b of the first passage 111 in the travelling direction
of the fiber bundle 34.
In order to ensure the restraint of the fiber
bundle 34, the length L1 of the plane portion 151 in the
first direction is preferably half or more of a length
30 L2 of the first passage 111 in the first direction.
In the configuration of FIG. 9, a downstream
26
portion 161 is formed in the vicinity of the downstream
end 111b on the inner surface of the first passage 111.
The downstream portion 161 is inclined with respect to
the plane portion 151, and linearly extends from the
5 downstream end 151a of the plane portion 151 to a part
of the downstream end 111b of the first passage 111
(position constituting a part of the contour of the
downstream opening of the first passage 111). The plane
portion 151 and the downstream portion 161 are connected
10 in a polygonal line shape as illustrated by a connection
portion 165 in FIG. 9, but may be connected by a smoothly
curve (e.g., in an arc shape). The downstream portion
161 may be formed into a smooth curved surface shape
instead of a flat surface.
15 The upstream end of the plane portion 151 may be
arranged so as to be located downstream relative to the
upstream end 111a of the first passage 111 in the
travelling direction of the fiber bundle 34. In this
case, as illustrated by the chain line in FIG. 9, an
20 upstream portion 162 is formed in the vicinity of the
upstream end 111a on the inner surface of the first
passage 111. The upstream portion 162 is inclined with
respect to the plane portion 151 and linearly extends
from the upstream end 111a of the first passage 111 to
25 the upstream end of the plane portion 151. The upstream
end of the upstream portion 162 constitutes a part of
the contour of the opening of the upstream end 111a of
the first passage 111. The upstream end of the upstream
portion 162 is arranged so as to be located away from
30 the fiber bundle 34 passing through the first passage
111, compared with the connection portion between the
27
upstream portion 162 and the plane portion 151. The
plane portion 151 and the upstream portion 162 may be
connected in a polygonal line shape, or may be connected
by a smooth curve. The upstream portion 162 may be
5 formed in a smooth curved surface shape instead of a
flat surface.
Regarding the width of the passage through which
the fiber bundle 34 passes, the cross-sectional area
(passage area) of the first passage 111 when the fiber
10 guide 101 is cut with a plane perpendicular to the first
direction is equal to or greater than 4 mm2 and equal to
or less than 7 mm2.
In the present embodiment, an interval S2 in the
direction of the shaft center 108 of the spindle between
15 the downstream end 111b of the first passage 111 and the
upstream end 122a of the second passage 122 is equal to
or greater than 0.3 mm and equal to or less than 7 mm.
The interval S2 can be made, for example, equal to or
greater than 1.1 mm and equal to or less than 2.5 mm, or
20 can be made equal to or greater than 4.2 mm and equal to
or less than 7 mm.
As described above, the pneumatic spinning device
23 of the present embodiment twists by the whirling
airflow the fiber passing through the spinning chamber
25 113, thereby forming the spun yarn 30. The pneumatic
spinning device 23 includes the fiber guide 101 and the
spindle 102. The fiber guide 101 has the first passage
111 through which the fiber bundle 34 passes. The
spindle 102 has the second passage 122 through which the
30 fiber bundle 34 having passed through the first passage
111 is guided, and the spindle 102 is provided so as to
28
face the fiber guide 101 across the spinning chamber 113.
The first passage 111 is provided so as to extend
linearly. The second passage 122 is provided so as to
extend along the shaft center 108 of the spindle 102
5 with the shaft center 108 as a center. The downstream
end 111b where the first passage 111 opens into the
spinning chamber 113 and the upstream end 122a where the
second passage 122 opens into the spinning chamber 113
are arranged at the interval S2 in the direction of the
10 shaft center 108 of the spindle 102. The inner surface
of the first passage 111 has the flat plane portion 151
on the side close to the shaft center 108 of the spindle
102. The angle of the linear portion obtained by cutting
the plane portion 151 with any plane perpendicular to
15 the first direction in which the first passage 111
extends with respect to the first direction is constant
between the upstream end 111a and the downstream end
111b of the first passage 111. The plane portion 151 is
arranged to deviate with respect to the shaft center 108
20 of the spindle 102 in the second direction perpendicular
to the direction of the shaft center 108 of the spindle
102. The interval S1 in the second direction between
the downstream end 151a of the plane portion 151 and the
shaft center 108 of the spindle 102 is equal to or
25 greater than 0.8 mm and equal to or less than 3.4 mm.
Accordingly, the fiber bundle 34 to be supplied to
the first passage 111 is restrained by coming into
contact with the flat plane portion 151 before reaching
the spinning chamber 113. Since the plane portion 151
30 is arranged to deviate with respect to the shaft center
108 of the spindle 102, when the fiber bundle 34 is
29
appropriately bent between the first passage 111 and the
second passage 122, the fiber bundle 34 is pressed well
with respective to the plane portion 151. Therefore,
even when the fiber bundle 34 is twisted by the whirling
5 airflow in the spinning chamber 113, it is possible to
effectively reduce propagation of the twist to the
upstream in the travelling direction. Thus, since the
fibers are not twisted upstream of the spinning chamber
113, separation and reversal of the fibers in the
10 spinning chamber 113 can be performed satisfactorily.
As a result, spinning can be stably performed.
In the pneumatic spinning device 23 of the present
embodiment, the interval S1 in the second direction
between the downstream end 151a of the plane portion 151
15 and the shaft center 108 of the spindle 102 is equal to
or greater than 0.9 mm and equal to or less than 1.5 mm.
In this case, the propagation of the twist
described above can be particularly effectively reduced.
In the pneumatic spinning device 23 of the present
20 embodiment, the plane portion 151 is arranged at a
position where the plane portion 151 and the opening
formed by the second passage 122 in the spinning chamber
113 do not appear to overlap each other when viewed in
the first direction.
25 Accordingly since the fiber bundle 34 can be
reliably bent between the first passage 111 and the
second passage 122, propagation of the twist to the
upstream can be reduced well.
In the pneumatic spinning device 23 of the present
30 embodiment, the cross-sectional shape of the first
passage 111 when the fiber guide 101 is cut with a plane
30
perpendicular to the first direction can be formed into
the shape illustrated in FIGS. 6A or 6B, for example.
In the cross-sectional shape illustrated in FIG. 6A,
provided that the distance in the direction orthogonal
5 to the linear portion corresponding to the plane portion
151 between the linear portion and the contour on the
opposite side of the linear portion across the first
passage 111 is called the gap length G, the gap length
G is constant over the entire longitudinal direction of
10 the linear portion (G1 = G2 = G3). In the crosssectional shape illustrated in FIG. 6B, the gap length
G at the longitudinal center of the linear portion
corresponding to the plane portion 151 is larger than
the gap length G at the longitudinal ends of the linear
15 portion (G1 > G2, G1 > G3).
Accordingly, the fiber bundle 34 can pass smoothly
while being restrained by the plane portion 151 in the
first passage 111.
In the pneumatic spinning device 23, the cross20 sectional shape of the first passage 111 is a quadrangle
shape or a D shape.
Accordingly, a simple configuration of the first
passage 111 can be realized.
In the pneumatic spinning device 23, the length L1
25 of the plane portion 151 in the first direction is equal
to or greater than 3 mm and equal to or less than 12 mm.
Accordingly, the plane portion 151 can reliably
exert the restraining action on the fiber bundle 34.
In the pneumatic spinning device 23 of the present
30 embodiment, the plane portion 151 is arranged to be
parallel to the shaft center 108 of the spindle 102 or
31
to be inclined at the angle θ1 equal to or less than 10°
with respect to the shaft center 108 of the spindle 102.
Accordingly, the fiber bundle 34 can be guided in
the first passage 111 well to the spinning chamber 113.
5 In the pneumatic spinning device 23 of the
alternative embodiment of FIG. 9, the downstream end
151a of the plane portion 151 is positioned upstream the
downstream end 111b of the first passage 111. The inner
surface of the first passage 111 has the plane portion
10 151 and the downstream portion 161. The downstream
portion 161 is inclined or curved with respect to the
plane portion 151 and extends from the downstream end
151a of the plane portion 151 to the downstream end 111b
of the first passage 111. The length L1 of the plane
15 portion 151 in the first direction is half or more of
the length L2 of the first passage 111 in the first
direction.
Accordingly, the fiber bundle 34 can be guided well
by the first passage 111 into the spinning chamber 113.
20 In the pneumatic spinning device 23 of the present
embodiment, the cross-sectional area (passage area) of
the first passage 111 when the fiber guide 101 is cut
with a plane perpendicular to the first direction is
equal to or greater than 4 mm2 and equal to or less than
25 7 mm2.
Accordingly, the fiber bundle 34 can pass through
the first passage 111 well.
In the pneumatic spinning device 23 of the present
embodiment, the interval S2 in the direction of the shaft
30 center 108 of the spindle 102 between the downstream end
111b of the first passage 111 and the upstream end 122a
32
of the second passage 122 is equal to or greater than
0.3 mm and equal to or less than 7 mm.
Accordingly, the fiber bundle 34 can be guided well
to the second passage 122. When the fiber bundle 34 is
5 guided to the second passage 122, to the fibers can be
reliably reversed and swirled by the whirling airflow
in the spinning chamber 113.
In the pneumatic spinning device 23 of the present
embodiment, the interval S2 can be equal to or greater
10 than 1.1 mm and equal to or less than 2.5 mm.
Accordingly, the fibers can be reliably reversed
and swirled in the spinning chamber 113 even if the
spinning speed is high.
In the pneumatic spinning device 23 of the present
15 embodiment, the interval S2 can be equal to or greater
than 4.2 mm and equal to or less than 7 mm.
In this case, spinning can be performed while the
fibers are reversed well.
The pneumatic spinning device 23 of the present
20 embodiment includes the nozzle block 103. The nozzle
block 103 has the spinning nozzle 131 through which air
can pass and arranged so as to form the spinning chamber
113 together with the fiber guide 101 and the spindle
102. The nozzle block 103 has an inner surface facing
25 the spinning chamber 113. The inner surface of the
nozzle block 103 is circular when viewed in a direction
along the shaft center 108 of the spindle 102. The inner
diameter D1 of the nozzle block 103 in this inner surface
portion is equal to or greater than 3 mm and equal to or
30 less than 9 mm.
Accordingly, spinning can be performed well.
33
In the pneumatic spinning device 23 of the present
embodiment, the spindle 102 is provided with the
auxiliary nozzle (passage hole) 135 through which air
can pass. The auxiliary nozzle 135 opens into the second
5 passage 122.
Accordingly, air can be supplied from the auxiliary
nozzle 135 to the second passage 122 such that the fiber
bundle 34 can travel through the second passage 122.
Therefore, it is possible to reliably perform the yarn
10 discharge spinning.
In the pneumatic spinning device 23 of the present
embodiment, the plurality of auxiliary nozzles 135 are
provided around the second passage 122.
Accordingly, airflow can be acted upon the fiber
15 bundle 34 in the second passage 122 in a well-balanced
manner, and the fiber bundle 34 can be delivered
downstream.
The pneumatic spinning machine 1 of the present
embodiment includes the pneumatic spinning device 23.
20 The pneumatic spinning machine 1 further includes the
suction pipe 87, the winding device 27, the suction mouth
89, and the yarn joining device 85. The suction pipe 87
catches the spun yarn 30 formed by the pneumatic spinning
device 23 at the time of yarn discharge spinning. The
25 winding device 27 winds, around the package 73, the spun
yarn 30 formed by the pneumatic spinning device 23. The
suction mouth 89 catches the spun yarn 30 wound around
the package 73. The yarn joining device 85 joins the
spun yarns 30 caught by the suction pipe 87 and the
30 suction mouth 89.
Thus, in the pneumatic spinning machine 1, which
34
performs yarn discharge spinning, even when the fibers
are twisted by the whirling airflow, it is possible to
effectively reduce propagation of the twist to the fibers
located upstream of the twisted fibers in the travelling
5 direction.
While the preferred embodiment of the present
invention has been described above, the structure
described above can be modified as below. The above
embodiment and the following modifications may be
10 combined as appropriate.
The pneumatic spinning device (pneumatic spinning
machine) may be configured to bring the spun yarn into
a continuous state by piecing after the spun yarn becomes
in a divided state. The piecing is a method of bringing
15 the spun yarn into a continuous state by sending back,
to the pneumatic spinning device, the spun yarn from the
package, and then restarting the draft by the draft
device and the spinning by the pneumatic spinning device.
The nozzle (passage hole) through which air is jetted
20 for piecing may be formed in the hollow guide shaft body.
That is, the auxiliary nozzle 135 described above may be
configured as such a nozzle by forming the direction of
the nozzle to be different from that of the above
embodiment. When piecing is performed, the yarn joining
25 device can be omitted.
The size, shape, and the like of the first passage
111 can be changed as appropriate. For example, the
cross-sectional shape of the first passage 111 may be an
asymmetrical shape in place of the line symmetrical shape
30 illustrated in FIGS. 6A, 6B, 7A and 7B.
As long as the angle of the linear portion
35
corresponding to the plane portion 151 with respect to
the first direction is constant, the cross-sectional
shape obtained by cutting the first passage 111 with any
plane perpendicular to the first direction may not be
5 uniform.
The auxiliary nozzle 135 may be omitted in the
spindle 102.
Although the inner surface 103a of the nozzle block
103 is configured to have a cylindrical shape, it may
10 include a taper shape widening towards downstream and/or
a step formed on the inner surface 103a.
Although the fiber guide 101 and the nozzle block
103 are illustrated as separate members in the drawings,
they may be formed by one member.
15 The configuration to draw the spun yarn 30 from
the pneumatic spinning device 23 is not limited to the
yarn accumulating device 25, and may be a delivery roller
pair. In this case, at least any of the yarn
accumulating device 25, a slack tube using suction
20 airflow, and a mechanical compensator may be provided
downstream of the delivery roller pair.
The configuration related to yarn joining may be
provided in each spinning unit 7 instead of the yarn
joining cart 9.
25 The “yarn” includes at least the spun yarn 30 and
a roving yarn.
The downstream end surface 115b of the body 115
may not be a flat surface. For example, at least one
protrusion projecting towards the spindle 102 may be
30 formed on the downstream end surface 115b. This
protrusion may have any shape and size. When the surface
36
of the projection end of the protrusion is substantially
connected to the downstream end 111b of the first passage
111, the height of the surface of the projection end can
be used as a reference (one end) of the interval S2
5 described above.
A concave and/or a recess may be formed on a part
or entirety of the downstream end surface 115b. The
concave and/or the recess can be realized by forming
elongated linear grooves and/or curved grooves, for
10 example. When the concave and/or the recess are
connected to the downstream end 111b of the first passage
111, the average height of the concave and/or the recess
at the connection portion may be used as a reference of
the interval S2 described above.
15 In consideration of the above teachings, it is
obvious that the present invention can have many
modifications and variations. Therefore, it should be
understood that within the scope of the appended claims,
the present invention can be carried out by the method
20 other than as described herein.
According to a first aspect of the present
invention, a pneumatic spinning device configured as
follows is provided. That is, this pneumatic spinning
device twists, by whirling airflow, the fibers passing
25 through the spinning chamber and forms a yarn. The
pneumatic spinning device includes a fiber guiding
section and a hollow guide shaft body. The fiber guiding
section has a first passage through which a fiber bundle
passes. The hollow guide shaft body has a second passage
30 through which the fiber bundle having passed through the
first passage is guided, and the hollow guide shaft body
37
is provided so as to face the fiber guiding section
across the spinning chamber. The first passage is
provided so as to extend linearly. The second passage
is provided so as to extend along a shaft center of the
5 hollow guide shaft body with the shaft center as a center.
A downstream end where the first passage opens into the
spinning chamber and an upstream end where the second
passage opens into the spinning chamber are arranged
with an interval in the direction of the shaft center of
10 the hollow guide shaft body. An inner surface of the
first passage has a flat plane portion on the side close
to the shaft center of the hollow guide shaft body. An
angle of a linear portion obtained by cutting the plane
portion with any plane perpendicular to a first direction
15 in which the first passage extends with respect to the
first direction is constant between an upstream end and
a downstream end of the first passage. The plane portion
is arranged to deviate with respect to the shaft center
of the hollow guide shaft body in a second direction
20 perpendicular to the direction of the shaft center of
the hollow guide shaft body. The interval in the second
direction between the downstream end of the plane portion
and the shaft center of the hollow guide shaft body is
equal to or greater than 0.8 mm and equal to or less
25 than 3.4 mm.
Accordingly, the fiber bundle having been supplied
to the first passage is restrained by coming into contact
with the flat plane portion before reaching the spinning
chamber. Since the plane portion is arranged to deviate
30 with respect to the shaft center of the hollow guide
shaft body, when the fiber bundle is appropriately bent
38
between the first passage and the second passage, the
fiber bundle is pressed well with respective to the plane
portion. Therefore, even when the fiber bundle is
twisted by the whirling airflow in the spinning chamber,
5 it is possible to effectively reduce propagation of the
twist to the upstream in the travelling direction. Thus,
since the fibers are not twisted upstream of the spinning
chamber, separation and reversal of the fibers in the
spinning chamber can be performed satisfactorily. As a
10 result, spinning can be stably performed.
In the pneumatic spinning device described above,
the interval in the second direction between the
downstream end of the plane portion and the shaft center
of the hollow guide shaft body is preferably equal to or
15 greater than 0.9 mm and equal to or less than 1.5 mm.
Accordingly, since the fiber bundle can be
appropriately bent between the first passage and the
second passage, the propagation of the twist described
above can be particularly effectively reduced.
20 In the pneumatic spinning device described above,
the plane portion is preferably arranged at a position
where the plane portion and an opening formed by the
second passage in the spinning chamber do not appear to
overlap each other when viewed in the first direction.
25 Accordingly, since the fiber bundle can be reliably
bent between the first passage and the second passage,
propagation of the twist to the upstream can be reduced
well.
In the pneumatic spinning device described above,
30 in a cross-sectional shape of the first passage when the
fiber guiding section is cut with a plane perpendicular
39
to the first direction, provided that a distance in a
direction orthogonal to the linear portion corresponding
to the plane portion between the linear portion and a
contour on the opposite side of the linear portion across
5 the first passage is called a gap length, the gap length
is preferably constant over the entire longitudinal
direction of the linear portion, or the gap length at
the longitudinal center of the linear portion is larger
than the gap length at longitudinal ends.
10 Accordingly, the fiber bundle can pass smoothly
while being restrained by the plane portion in the first
passage.
In the pneumatic spinning device described above,
the cross-sectional shape of the first passage is
15 preferably a quadrangle shape or a D shape.
Accordingly, a simple configuration of the first
passage can be realized.
In the pneumatic spinning device described above,
the length of the plane portion in the first direction
20 is preferably equal to or greater than 3 mm and equal to
or less than 12 mm.
Accordingly, the plane portion can reliably exert
the restraining action on the fiber bundle.
In the pneumatic spinning device described above,
25 the plane portion is preferably arranged so as to be in
parallel to the shaft center direction of the hollow
guide shaft body or to be inclined at an angle of equal
to or less than 10° with respect to the direction of the
shaft center of the hollow guide shaft body.
30 Accordingly, the fiber bundle can be guided in the
first passage well to the spinning chamber.
40
The pneumatic spinning device described above
preferably has the following configuration. That is,
the downstream end of the plane portion is positioned in
the first passage and upstream of the downstream end of
5 the first passage. The inner surface of the first
passage has the plane portion and a downstream portion
that is inclined or curved with respect to the plane
portion and extends from the downstream end of the plane
portion to the downstream end of the first passage
10 towards the upstream end of the second passage. The
length of the plane portion in the first direction is
equal to or greater than half the length of the first
passage in the first direction.
Accordingly, the fiber bundle can be guided in the
15 first passage well to the spinning chamber.
In the pneumatic spinning device described above,
the passage area of the first passage when the fiber
guiding section is cut with a plane perpendicular to the
first direction is preferably equal to or greater than
20 4 mm2 and equal to or less than 7 mm2.
Accordingly, the fiber bundle can pass through the
first passage well.
In the pneumatic spinning device described above,
the interval in the first direction between the
25 downstream end of the first passage and the upstream end
of the second passage is preferably equal to or greater
than 0.3 mm and equal to or less than 7 mm.
Accordingly, the fiber bundle can be guided well
to the second passage. When the fiber bundle is guided
30 to the second passage, the fibers can be reliably
reversed and swirled by the whirling airflow in the
41
spinning chamber.
In the pneumatic spinning device described above,
the interval in the first direction between the
downstream end of the first passage and the upstream end
5 of the second passage can be equal to or greater than
1.1 mm and equal to or less than 2.5 mm.
Accordingly, the fibers can be reliably reversed
and swirled in the spinning chamber even if the spinning
speed is high.
10 In the pneumatic spinning device described above,
the interval in the first direction between the
downstream end of the first passage and the upstream end
of the second passage can be equal to or greater than
4.2 mm and equal to or less than 7 mm.
15 In this case, spinning can be performed while the
fibers are reversed well.
The pneumatic spinning device described above
preferably has the following configuration. That is,
the pneumatic spinning device includes a casing having
20 a spinning nozzle through which air can pass and arranged
so as to form the spinning chamber together with the
fiber guiding section and the hollow guide shaft body.
The casing has an inner surface facing the spinning
chamber. The inner surface of the casing is circular
25 when viewed in a direction along the shaft center of the
hollow guide shaft body. An inner diameter of the casing
in the inner surface portion is equal to or greater than
3 mm and equal to or less than 9 mm.
Accordingly, spinning can be performed well.
30 The pneumatic spinning device described above
preferably has the following configuration. That is,
42
the hollow guide shaft body is formed with a passage
hole through which air can pass. The passage hole opens
into the second passage.
Accordingly, air can be supplied to the second
5 passage through the passage hole such that the fiber
bundle can travel through the second passage.
In the pneumatic spinning device described above,
a plurality of the passage holes are preferably provided
around the second passage.
10 Accordingly, airflow can act on the fiber bundle
in the second passage in a well-balanced manner.
According to a second aspect of the present
invention, a pneumatic spinning machine configured as
follows is provided. That is, this pneumatic spinning
15 machine includes the pneumatic spinning device described
above. This pneumatic spinning machine includes a first
catching device, a winding device, a second catching
device, and a yarn joining device. The first catching
device catches a yarn formed by the pneumatic spinning
20 device at the time of yarn discharge spinning. The
winding device winds the yarn formed by the pneumatic
spinning device. The second catching device catches the
wound yarn. The yarn joining device joins the yarn
caught by the first catching device and the yarn caught
25 by the second catching device.
Thus, in the pneumatic spinning machine that
performs yarn discharge spinning, even when the fibers
are twisted by the whirling airflow, it is possible to
effectively reduce propagation of the twist to the fibers
30 located upstream of the twisted fibers in the travelling
direction.

WE CLAIM
1. A pneumatic spinning device (23) that forms a
yarn (30) by twisting, by whirling airflow, fibers
passing through a spinning chamber (113), the pneumatic
5 spinning device (23) comprising:
a fiber guiding section (101) having a first
passage (111) through which a fiber bundle (34) passes;
and
a hollow guide shaft body (102) that has a second
10 passage (122) through which the fiber bundle (34) having
passed through the first passage (111) is guided, and
that is provided so as to face the fiber guiding section
(101) across the spinning chamber (113), wherein
the first passage (111) is provided so as to extend
15 linearly,
the second passage (122) is provided so as to
extend along a shaft center (108) of the hollow guide
shaft body (102) with the shaft center (108) as a center,
a downstream end (111b) where the first passage
20 (111) opens into the spinning chamber (113) and an
upstream end (122a) where the second passage (122) opens
into the spinning chamber (113) are arranged with an
interval (S1) in a direction of the shaft center (108)
of the hollow guide shaft body (102),
25 an inner surface of the first passage (111) has a
flat plane portion (151) on a side close to the shaft
center (108) of the hollow guide shaft body (102),
an angle of a linear portion obtained by cutting
the plane portion (151) with any plane perpendicular to
30 a first direction in which the first passage (111)
extends with respect to the first direction is constant
44
between an upstream end (111a) and the downstream end
(111b) of the first passage (111),
the plane portion (151) is arranged to deviate with
respect to the shaft center (108) of the hollow guide
5 shaft body (102) in a second direction perpendicular to
a direction of the shaft center (108) of the hollow guide
shaft body (102), and
an interval (S1) in the second direction between a
downstream end (151a) of the plane portion (151) and the
10 shaft center (108) of the hollow guide shaft body (102)
is equal to or greater than 0.8 mm and equal to or less
than 3.4 mm.
2. The pneumatic spinning device (23) as claimed
15 in claim 1, wherein the interval (S1) in the second
direction between the downstream end (151a) of the plane
portion (151) and the shaft center (108) of the hollow
guide shaft body (102) is equal to or greater than 0.9
mm and equal to or less than 1.5 mm.
20
3. The pneumatic spinning device (23) as claimed
in claim 1 or 2, wherein the plane portion (151) is
arranged at a position where the plane portion (151) and
an opening formed by the second passage (122) in the
25 spinning chamber (113) do not appear to overlap each
other when viewed in the first direction.
4. The pneumatic spinning device (23) as claimed
in any one of claims 1 to 3, wherein in a cross-sectional
30 shape of the first passage (111) when the fiber guiding
section (101) is cut with a plane perpendicular to the
45
first direction, provided that a distance in a direction
orthogonal to a linear portion corresponding to the plane
portion (151) between the linear portion and a contour
on an opposite side of the linear portion across the
5 first passage (111) is called a gap length (G), a gap
length (G) is constant over an entire longitudinal
direction of the linear portion, or a gap length (G1) at
a longitudinal center of the linear portion is larger
than a gap length (G2; G3) at a longitudinal end.
10
5. The pneumatic spinning device (23) as claimed
in claim 4, wherein a cross-sectional shape of the first
passage (111) is a quadrangle shape or a D shape.
15 6. The pneumatic spinning device (23) as claimed
in any one of claims 1 to 5, wherein a length of the
plane portion (151) in the first direction is equal to
or greater than 3 mm and equal to or less than 12 mm.
20 7. The pneumatic spinning device (23) as claimed
in any one of claims 1 to 6, wherein the plane portion
(151) is arranged so as to be in parallel to the
direction of the shaft center (108) of the hollow guide
shaft body (102) or to be inclined at an angle (θ1) equal
25 to or less than 10° with respect to the direction of the
shaft center (108) of the hollow guide shaft body (102).
8. The pneumatic spinning device (23) as claimed
in claim 6, wherein
30 the downstream end (151a) of the plane portion
(151) is positioned in the first passage (111) and
46
upstream of the downstream end (111b) of the first
passage (111),
an inner surface of the first passage (111) has
the plane portion (151), and
5 a downstream portion (161) inclined or curved with
respect to the plane portion (151) and extending from
the downstream end (151a) of the plane portion (151) to
the downstream end (111b) of the first passage (111),
and
10 a length (L1) of the plane portion (151) in the
first direction is equal to or greater than half a length
(L2) of the first passage (111) in a first direction.
9. The pneumatic spinning device (23) as claimed
15 in any one of claims 1 to 8, wherein a passage area of
the first passage (111) when the fiber guiding section
(101) is cut with a plane perpendicular to the first
direction is equal to or greater than 4 mm2 and equal to
or less than 7 mm2.
20
10. The pneumatic spinning device (23) as claimed
in any one of claims 1 to 9, wherein an interval (S2) in
the first direction between a downstream end (111b) of
the first passage (111) and an upstream end (122a) of
25 the second passage (122) is equal to or greater than 0.3
mm and equal to or less than 7 mm.
11. The pneumatic spinning device (23) as claimed
in claim 10, wherein the interval (S2) in the first
30 direction between the downstream end (111b) of the first
passage (111) and the upstream end (122a) of the second
47
passage (122) is equal to or greater than 1.1 mm and
equal to or less than 2.5 mm.
12. The pneumatic spinning device (23) as claimed
5 in claim 10, wherein the interval (S2) in the first
direction between the downstream end (111b) of the first
passage (111) and the upstream end (122a) of the second
passage (122) is equal to or greater than 4.2 mm and
equal to or less than 7 mm.
10
13. The pneumatic spinning device (23) as claimed
in any one of claims 1 to 12, comprising:
a casing (103) having a spinning nozzle (131)
through which air can pass and arranged so as to form
15 the spinning chamber (113) together with the fiber
guiding section (101) and the hollow guide shaft body
(102), wherein
the casing (103) has an inner surface facing the
spinning chamber (113),
20 the inner surface of the casing (103) is circular
when viewed in a direction along the shaft center (108)
of the hollow guide shaft body (102), and
an inner diameter of the casing (103) in the inner
surface portion is equal to or greater than 3 mm and
25 equal to or less than 9 mm.
14. The pneumatic spinning device (23) as claimed
in any one of claims 1 to 13, wherein the hollow guide
shaft body (102) is formed with a passage hole (135)
30 through which air can pass, and the passage hole (135)
opens into the second passage (122).
48
15. The pneumatic spinning device (23) as claimed
in claim 14, wherein a plurality of the passage holes
(135) are provided around the second passage (122).
5
16. A pneumatic spinning machine (1) including
the pneumatic spinning device (23) as claimed in any one
of claims 1 to 15, comprising:
a first catching device (87) adapted to catch a
10 yarn (30) formed by the pneumatic spinning device (23)
at a time of yarn discharge spinning;
a winding device (27) adapted to wind a yarn (30)
formed by the pneumatic spinning device (23);
a second catching device (89) adapted to catch a
15 wound yarn (30); and
a yarn joining device (85) adapted to join the yarn
(30) caught by the first catching device (87) and the
yarn (30) caught by the second catching device (89).