BACKGROUND OF THE INVENTION
1. Field of the Invention
[0001] The present invention relates to an air spinning machine. More specifically, the
present invention relates to a structure for supplying compressed air to air injection
holes of the air spinning machine.
2. Description of the Related Art
[0002] Patent Document 1 (Japanese Unexamined Patent Application Publication No.
2005-220483) discloses an air spinning machine that includes a spinning chamber, which is formed
in a substantially circular shape in cross section, and that injects compressed air
from a plurality of whirling flow generation nozzles (air injection holes) to the
spinning chamber, in a tangential direction of the spinning chamber in order to generate
whirling airflow in the spinning chamber to apply twists to a fiber bundle.
[0003] Fig. 6 is a schematic cross-sectional plan view of a spinning device of a conventional
air spinning machine. A spinning device 93 includes a spinning chamber 94 formed in
a substantially circular shape in cross section. A fiber bundle 98 can be inserted
into the spinning chamber 94 in a direction perpendicular to the plane of Fig. 6.
An air chamber 95 is formed in a ring shape in cross section around the spinning chamber
94. The spinning chamber 94 and the air chamber 95 are connected by a plurality of
elongate whirling flow generation nozzles (air injection holes) 96. The whirling flow
generation nozzle 96 is formed in a tangential direction of the spinning chamber 94
in planar view. A compressed air supplying pipe 97 is connected to the ring-shaped
air chamber 95 so as to supply compressed air from a not-illustrated compressed air
source to the air chamber 95.
[0004] In the above-described structure, when the compressed air is supplied from the compressed
air supplying pipe 97 to the air chamber 95, the compressed air is divided and supplied
from the air chamber 95 to the plurality of whirling flow generation nozzles 96, and
then, the compressed air is injected from each of the whirling flow generation nozzles
96 towards the spinning chamber 94. Thus, for example, counterclockwise whirling airflow
is generated in the spinning chamber 94 as indicated by an arrow of the drawing. The
spinning device 93 can produce spun yarn by applying twists to the fiber bundle 98
by the whirling airflow.
[0005] The whirling flow generation nozzle 96 is slanted towards the inner side of the plane
of Fig. 6. Accordingly, when the compressed air is injected from the whirling flow
generation nozzles 96 to the spinning chamber 94, airflow directed to the inner side
of the plane of Fig. 6 is generated in the spinning chamber 94. Thus, the spinning
chamber 94 is decompressed, i.e. the pressure inside the spinning chamber 94 is decreased
(Bernoulli's theory), and the fiber bundle 98 can be sucked and guided into the spinning
chamber 94.
[0006] However, in such an air spinning machine, when an amount (i.e. quantity or volume)
of the compressed air supplied from the compressed air supplying pipe increases due
to an increase in a spinning speed, or the like, an amount of the airflow injected
from the plurality of whirling flow generation nozzles to the spinning chamber may
be unequalized. As a result, the whirling flow may become turbulent in the spinning
chamber, decreasing stability of a spinning operation. Moreover, since the spinning
chamber is not sufficiently decompressed, a stable suction operation may become difficult.
SUMMARY OF THE INVENTION
[0007] In order to overcome the problems described above, preferred embodiments of the present
invention provide an air spinning machine that can perform a spinning operation and
a suction operation stably and in good condition even when an amount of airflow increases.
[0008] According to an aspect of the present invention, an air spinning machine includes
a spinning chamber, a hollow guide spindle, a first air chamber, a second air chamber,
a plurality of air channels, and a plurality of air injection holes. Compressed air
is supplied to the first air chamber. The air channels connect the first air chamber
and the second air chamber. The air injection holes connect the second air chamber
and the spinning chamber.
[0009] Thus, since the compressed air can be supplied from the plurality of air channels
to the second air chamber, an amount (i.e. quantity or volume) of the airflow injected
from the plurality of air injection holes to the spinning chamber can be equalized,
and even when the amount of airflow increases, the spinning operation and the suction
operation can be performed stably and in good condition. As a result, the quality
of a spun yarn produced by spinning a fiber bundle in the spinning chamber can be
maintained in good condition.
[0010] In the air spinning machine, a total cross-sectional area of the plurality of the
air channels is preferably greater than a total cross-sectional area of the plurality
of the air injection holes. Thus, the pressure inside the second air chamber can be
equalized in good condition, and the amount of the airflow injected from the plurality
of the air injection holes can be further equalized.
[0011] In the air spinning machine, the second air chamber is preferably formed in a ring
shape around the spinning chamber. The air channels are preferably arranged at equal
interval in a peripheral direction of the second air chamber. Thus, since the compressed
air can be equally supplied to the second air chamber in a peripheral direction of
the second air chamber, the air pressure inside the second air chamber can be equalized
in good condition, and the amount of the airflow injected from the plurality of air
injection holes can be equalized.
[0012] In the air spinning machine, the first air chamber is preferably formed in a ring
shape outside the second air chamber in a radial direction of the second air chamber.
Accordingly, a device that is compact in a traveling direction of a fiber bundle or
of a spun yarn can be provided.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Fig. 1 is a front view of an entire structure of a spinning machine according to
an embodiment of the present invention.
[0014] Fig. 2 is a longitudinal cross-sectional view of the spinning machine.
[0015] Fig. 3 is a longitudinally-cross-sectional front view of a spinning section.
[0016] Fig. 4 is a longitudinally-cross-sectional front view illustrating a state of the
spinning section during a spinning operation.
[0017] Fig. 5 is a schematic cross-sectional plan view of the spinning section.
[0018] Fig. 6 is a schematic cross-sectional plan view of a spinning section of a conventional
air spinning machine.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0019] Next, an embodiment of the present invention will be described with reference to
the drawings. A spinning machine 1 as an air spinning machine illustrated in Fig.
1 includes a plurality of aligned spinning units (air spinning units) 2. The spinning
machine 1 further includes a yarn splicing cart 3, a blower box 4, and a motor box
5. The yarn splicing cart 3 can travel in a direction in which the spinning units
2 are aligned.
[0020] As illustrated in Fig. 1, each of the spinning units 2 primarily includes a draft
device 7, a spinning section 9, a yarn feeding device 11, and a winding device 12.
The draft device 7 is provided at an upper portion of a frame 6 of the spinning machine
1. The spinning section 9 spins a fiber bundle 8 fed from the draft device 7. A spun
yarn 10 fed from the spinning section 9 is further fed by the yarn feeding device
11, and then wound by the winding device 12 into a package 45.
[0021] The draft device 7 drafts a sliver 13 into the fiber bundle 8. As illustrated in
Fig. 2, the draft device 7 includes a back roller 14, a third roller 15, a middle
roller 17, and a front roller 18. Further, an apron belt 16 is wound around the middle
roller 17.
[0022] A draft motor 31 formed of an electric motor is provided at an appropriate position
of the frame 6. The back roller 14 and the third roller 15 are connected to the draft
motor 31 via a belt. A unit controller 32 of the spinning unit 2 controls to drive
and stop the draft motor 31. In the spinning machine 1 according to the present embodiment,
although an electric motor for driving the middle roller 17 and the front roller 18
is also provided on the frame 6, illustration thereof is omitted.
[0023] The yarn feeding device 11 includes a delivery roller 39 and a nip roller 40. The
delivery roller 39 is supported on the frame 6 of the spinning machine 1. The nip
roller 40 is in contact with the delivery roller 39. While the spun yarn 10 discharged
from the spinning section 9 is nipped between the delivery roller 39 and the nip roller
40, the delivery roller 39 is rotationally driven by a not-illustrated electric motor.
Accordingly, the spun yarn 10 can be fed to the winding device 12.
[0024] As illustrated in Figs. 1 and 2, the yarn splicing cart 3 includes a splicer (yarn
splicing device) 43, a suction pipe 44, and a suction mouth 46. The yarn splicing
cart 3 travels on a rail 41 provided on the frame 6 of a main body of the spinning
machine 1. When a yarn cutting or a yarn breakage occurs in a certain spinning unit
2, the yarn splicing cart 3 travels to and stops at such a spinning unit 2. While
vertically swinging around a shaft, the suction pipe 44 sucks and catches a yarn end
discharged from the spinning section 9, and then guides the caught yarn end to the
splicer 43. While vertically swinging around a shaft, the suction mouth 46 sucks and
catches a yarn end from the package 45, which is rotationally supported by the winding
device 12, and then the suction mouth 46 guides the caught yarn end to the splicer
43. The splicer 43 splices the guided yarn ends.
[0025] As illustrated in Fig. 2, the spinning section 9 is divided into two blocks, that
is, a first block 91 and a second block 92. The second block 92 is provided downstream
of the first block 91 in a direction in which the fiber bundle 8 is fed.
[0026] Apneumatic cylinder 80 is connected to the second block 92. By driving the pneumatic
cylinder 80, the second block 92 can be moved away from the first block 91. When fibers
or the like clog a later-described air discharging space 55, whirling flow generation
chamber 25, or spinning chamber 26, which are formed between the first block 91 and
the second block 92, by moving the second block 92 away from the first block 91, maintenance
work such as a cleaning operation etc. can be easily performed. The pneumatic cylinder
80 is controlled by the unit controller 32 and can be operated in accordance with
a proper drive signal.
[0027] Next, with reference to Figs. 3 through 5, a structure of the spinning section 9
will be described further in detail. As illustrated in Fig. 3, the first block 91
includes an air spinning nozzle 19, a nozzle casing 53, and a ring member 63. The
second block 92 includes a hollow guide spindle 20 and a spindle holding member 59.
[0028] The air spinning nozzle 19 includes a needle holder 23 and a nozzle block 34. The
air spinning nozzle 19 is supported by the nozzle casing 53. A guide hole 21 is formed
in the needle holder 23. The fiber bundle 8, which has been drafted by the draft device
7 arranged upstream, is introduced into the guide hole 21. The needle holder 23 holds
a needle 22 arranged on a path of the fiber bundle 8 introduced from the guide hole
21.
[0029] A taper hole 54 is formed in the nozzle block 34 at a position located downstream
of the path of the fiber bundle 8 than the needle holder 23. A tip end portion 24
of the hollow guide spindle 20 is coaxially inserted into the taper hole 54. The tip
end portion 24 is formed in a taper shape, and its taper angle is substantially similar
to a taper angle of the taper hole 54. The round-shaped (circular) spinning chamber
26 is formed between a tip end surface of the hollow guide spindle 20 and the needle
holder 23. A tip end of the needle 22 protrudes into the spinning chamber 26. The
tip end of the needle 22 faces the tip end surface of the hollow guide spindle 20.
[0030] The tip end portion 24 of the hollow guide spindle 20 is arranged such that prescribed
space is formed between the hollow guide spindle 20 and the taper hole 54. Accordingly,
the whirling flow generation chamber (hollow chamber) 25 is formed and connected to
the spinning chamber 26. The air discharging space 55 is formed in the nozzle casing
53. The air discharging space 55 is connected to the whirling flow generation chamber
25. The air discharging space 55 is connected via a pipe 60 to a not-illustrated negative-pressure
source (suction mechanism) provided in the blower box 4.
[0031] The hollow guide spindle 20 includes a tubular body 56. The taper-shaped tip end
portion 24 is formed at one end of the tubular body 56. A yarn path 29 is formed at
the shaft center of the hollow guide spindle 20. After passing through the yarn path
29, the yarn is discharged through a not-illustrated outlet hole arranged downstream.
The tubular body 56 includes a large radial portion 58 having an enlarged radius at
a downstream side than the tip end portion 24. The large radial portion 58 is exposed
to the air discharging space 55. Under a state in which the large radial portion 58
is inserted into the spindle holding member 59, the hollow guide spindle 20 is fixed
relative to the spindle holding member 59.
[0032] The ring member 63 is formed in a ring shape in cross section in a plane perpendicular
to the traveling direction of the fiber bundle 8, and can be engaged with the nozzle
casing 53. A plurality of holes (air channels) 64, which are elongate in a radial
direction of the ring member 63, are formed (drilled) in the ring member 63 so as
to connect an inner periphery and an outer periphery of the ring member 63. More specifically,
as illustrated in Fig. 5, eight air channels 64 are arranged at equal interval in
a peripheral direction of the ring member 63. Each of the eight air channels 64 has
a similar channel cross-sectional area and a similar length. Further, the channel
cross-sectional area and the length of each of the eight air channels 64 may be identical.
[0033] As illustrated in Figs. 3 and 5, when the ring member 63 is engaged with the nozzle
casing 53, a ring-shaped first air chamber 61 is formed between the ring member 63
and the nozzle casing 53, and a ring-shaped second air chamber 62 is formed between
the nozzle block 34 and the ring member 63. A compressed air supplying pipe 65, which
is connected to a not-illustrated compressed air source, is connected with the nozzle
casing 53. Accordingly, compressed air can be supplied from the compressed air source
to the first air chamber 61.
[0034] A plurality of whirling flow generation nozzles (air injection holes) 27 are formed
in the nozzle block 34 to connect the spinning chamber 26 and the second air chamber
62. The whirling flow generation nozzles 27 are an elongate hole formed (drilled)
in the nozzle block 34. As illustrated in Fig. 3, a longitudinal direction of the
whirling flow generation nozzles 27 is slightly slanted towards a downstream side
of a yarn feeding direction, and as illustrated in Fig. 5, the whirling flow generation
nozzles 27 are formed in a tangential direction of the round-shaped spinning chamber
26.
[0035] The whirling flow generation nozzles 27 inject the compressed air supplied from the
compressed air source to the spinning chamber 26, and, for example, the whirling flow
generation nozzles 27 generate whirling flow directed in a counterclockwise direction
in planar view in the spinning chamber 26 (refer to Figs. 4 and 5). After spirally
flowing downstream along the whirling flow generation chamber 25, the whirling flow
is discharged from the air discharging space 55 formed in the nozzle casing 53. Further,
the spinning chamber 26 is decompressed by the airflow directed downstream, and suction
flow is generated in the guide hole 21.
[0036] Focusing on the arrangement of the spinning chamber 26, the first air chamber 61,
and the second air chamber 62, the spinning section 9 is configured as follows. That
is, the ring-shaped second air chamber 62 is formed around the round-shaped spinning
chamber 26, and the spinning chamber 26 and the second air chamber 62 are connected
via the plurality of whirling flow generation nozzles 27. Moreover, the ring-shaped
first air chamber 61 is formed around the second air chamber 62, and the first air
chamber 61 and the second air chamber 62 are connected via the plurality of air channels
64.
[0037] When the compressed air is supplied from the compressed air source via the compressed
air supplying pipe 65 to the first air chamber 61, the compressed air supplied to
the first air chamber 61 is supplied to the second air chamber 62 via the plurality
of air channels 64. Then, the compressed air can be injected from the second air chamber
62 to the spinning chamber 26 through the plurality of whirling flow generation nozzles
27.
[0038] A description will now be made of advantages of the structure in which the compressed
air is supplied to the spinning chamber via the two air chambers as described above.
[0039] As illustrated in Fig. 6, a conventional air spinning machine includes only one air
chamber 95, and the compressed air is supplied through one compressed air supplying
pipe 97 to the air chamber 95. However, in the air chamber 95 having such a structure,
a pressure difference is generated between a position located near a connection portion
of the compressed air supplying pipe 97 and a position located away from such a connection
portion. As a result, an amount (i.e. quantity or volume) of the airflow injected
from each of a plurality of whirling flow generation nozzles 96 varies and, in particular,
when a large amount of compressed air is supplied, the varying in the amount of the
airflow becomes significant, causing unstable whirling flow and suction flow.
[0040] On this point, in the present embodiment, as illustrated in Fig. 5, the compressed
air is once supplied to the first air chamber 61, and then supplied from the first
air chamber 61 to the second air chamber 62 via the plurality of air channels 64 provided
as an orifice (flow adjusting section). Accordingly, after distributing the compressed
air to some degree in the peripheral direction in the ring-shaped first air chamber
61 (i.e., after moderating a pressure difference to some degree in the peripheral
direction), the compressed air can be supplied to the second air chamber 62. In particular,
in the present embodiment, the plurality of air channels 64 are arranged at equal
interval in the peripheral direction of the ring-shaped second air chamber 62. Thus,
since the compressed air can be supplied to the second air chamber 62 equally in the
peripheral direction, disproportion or unevenness of the air pressure in the second
air chamber 62 can be eliminated. As a result, the amount of the compressed air injected
from the whirling flow generation nozzles 27 can be equalized.
[0041] In the present embodiment, a total cross-sectional area of the plurality of air channels
64 is greater than a total cross-sectional area of the plurality of whirling flow
generation nozzles 27. Accordingly, when the compressed air is introduced into the
whirling flow generation nozzles 27, the amount of the airflow is squeezed. Thus,
the air pressure inside the second air chamber 62 located upstream can be further
equalized. As a result, the amount of the compressed air injected from the whirling
flow generation nozzles 27 can be further equalized.
[0042] Next, an operation of spinning the fiber bundle 8 by the above-described spinning
section 9 will be described.
[0043] First, under a state in which a fiber bundle 8 has not been introduced into the spinning
section 9 (illustrated in Fig. 3), the compressed air is supplied from the not-illustrated
compressed air source, and further injected to the spinning chamber 26 by the whirling
flow generation nozzles 27. Thus, the whirling airflow is generated in the spinning
chamber 26, and airflow flowing downward in the drawing of Fig. 3 is generated. Accordingly,
the spinning chamber 26 is decompressed by Bernoulli's theory, and suction flow is
generated in the guide hole 21. In this state, when the fiber bundle 8 is fed from
the draft device 7 to the spinning section 9, the fiber bundle 8 is sucked into the
guide hole 21 and guided to the spinning chamber 26. The fiber bundle 8 introduced
into the spinning chamber 26 passes through the yarn path 29, and is eventually discharged
from the not-illustrated outlet hole to the outside of the spinning section 9.
[0044] A yarn end discharged from the outlet hole of the spinning section 9 is caught by
the suction pipe 44 of the yarn splicing cart 3, and spliced with a yarn end of the
package 45 by the splicer 43. Accordingly, the fiber bundle 8 or the spun yarn 10
is connected from the front roller 18 to the yarn feeding device 11 via the guide
hole 21, the spinning chamber 26, and the yarn path 29. In this state, by applying
a feeding force to the spun yarn 10 by the yarn feeding device 11 towards the downstream
side, tension is applied to the spun yarn 10, and the spun yarn 10 is sequentially
fed from the spinning section 9.
[0045] As illustrated in Fig. 4, the fiber bundle 8 fed from the front roller 18 of the
draft device 7 towards the downstream side enters the spinning chamber 26 through
the guide hole 21, and the whirling flow generated by the whirling flow generation
nozzles 27 acts upon the fiber bundle 8. Accordingly, one end of each of short fibers
is separated and opened relative to long fibers defined as core fibers of the fiber
bundle 8. The short fibers are swung around in the whirling flow generation chamber
25, and twists are applied to the fibers. Such twists tend to be propagated towards
the front roller 18, however, the propagation is prevented by the needle 22. Therefore,
the fiber bundle 8 fed from the front roller 18 is not twisted in by such twists.
As described above, the needle 22 has a twist propagation preventing function. However,
such a twist propagation preventing function is not limited to the needle 22, and
may be achieved by other structures.
[0046] Such twisted fibers are sequentially produced into a truly-twisted yarn, in which
most of the fibers are wound fibers. Such a truly-twisted yarn passes through the
yarn path 29 as the spun yarn 10, and then, the spun yarn 10 is discharged from the
not-illustrated outlet hole to the downstream side. After passing through the yarn
feeding device 11 of Fig. 1, the spun yarn 10 is wound by the winding device 12 and
eventually formed into the package 45. Further, there are fibers that are not twisted
into the spun yarn 10 due to breakage or the like that occurs when the short fibers
are opened or when the twists are applied. Such fibers are fed from the whirling flow
generation chamber 25 to the air discharging space 55 by the whirling flow generated
by the whirling flow generation nozzles 27, and then, discharged via the pipe 60 by
the suction of the negative-pressure source.
[0047] As described above, the spinning machine 1 according to the present embodiment includes
the spinning chamber 26, the hollow guide spindle 20, the first air chamber 61, the
second air chamber 62, the plurality of air channels 64, and the plurality of whirling
flow generation nozzles 27. The compressed air is supplied to the first air chamber
61. Each of the plurality of air channels 64 connects the first air chamber 61 and
the second air chamber 62. Each of the plurality of whirling flow generation nozzles
27 connects the second air chamber 62 and the spinning chamber 26.
[0048] As described above, the compressed air can be supplied from the plurality of air
channels 64 to the second air chamber 62. Thus, the amount of the airflow injected
from the plurality of whirling flow generation nozzles 27 into the spinning chamber
26 can be equalized, and even if the amount of the airflow increases, the spinning
operation and the suction operation can be stably performed. As a result, the quality
of the spun yarn 10 produced by spinning the fiber bundle 8 in the spinning chamber
26 can be maintained in good condition.
[0049] In the spinning machine 1 according to the present embodiment, the total cross-sectional
area of the plurality of air channels 64 is greater than the total cross-sectional
area of the plurality of whirling flow generation nozzles 27. Therefore, the pressure
inside the second air chamber 62 can be equalized in good condition, and the amount
of the airflow injected from the plurality of whirling flow generation nozzles 27
can be further equalized.
[0050] In the spinning machine 1 according to the present embodiment, the spinning chamber
26 is formed in a substantially round shape in cross section. The second air chamber
62 is formed in a ring shape around the spinning chamber 26. The air channels 64 are
arranged at equal interval in the peripheral direction of the second air chamber 62.
Thus, the compressed air can be supplied to the second air chamber 26 equally in the
peripheral direction. As a result, the air pressure inside the second air chamber
62 can be equalized in good condition, and the amount of the airflow injected from
the plurality of whirling flow generation nozzles 27 into the second air chamber 26
can be equalized.
[0051] In the spinning machine 1 according to the present embodiment, the first air chamber
61 is formed in a ring shape outside the second air chamber 62 in the radial direction
of the second air chamber 62. Accordingly, a device that is compact in the traveling
direction of the fiber bundle or of the spun yarn can be provided.
[0052] The preferred embodiment of the present invention has been described above, however,
for example, the above-described structures may be modified as follows.
[0053] The number of the whirling flow generation nozzles 27 and the number of air channels
64 are not limited to those in the above-described embodiment, but may be appropriately
changed.
[0054] The air channels, which connect the first air chamber and the second air chamber,
are not necessarily required to be arranged at equal interval as long as a plurality
of air channels are provided. However, from the standpoint of equally supplying the
compressed air to the second air chamber, it is preferable to arrange the air channels
at equal interval in the peripheral direction of the second air chamber as described
in the above embodiment.
[0055] Instead of forming the first air chamber around the second air chamber, for example,
the first air chamber may be formed downstream in the yarn traveling direction (lower
side in the drawing of Fig. 3) relative to the second air chamber, and the first air
chamber and the second air chamber may be connected by a plurality of air channels
formed parallel to the yarn traveling direction. However, from the standpoint of downsizing
the spinning section in the yarn traveling direction and the standpoint of having
the airflow to smoothly flow from the compressed air supplying pipe to the whirling
flow generation nozzles, the first air chamber is preferably arranged around the second
air chamber.
[0056] In the above-described embodiment, the position of the ring member 63 is not fixed
in the peripheral direction. Accordingly, a positional relationship of the air channels
64 and the whirling flow generation nozzles 27 is not limited to the positional relationship
illustrated in Fig. 5. However, when fixing the position of the ring member 63 in
the peripheral direction, it is preferable that an opening end of the air channel
64 and an opening end of the whirling flow generation nozzle 27 do not face one another
as illustrated in Fig. 5. Accordingly, the airflow from the air channels 64 does not
directly flow into the whirling flow generation nozzles 27. As a result, the amount
of the compressed air injected from the whirling flow generation nozzles 27 can be
further equalized.