Field of the Invention
[0001] The present invention relates to a spinning machine that manufactures spun yarns
utilizing whirling air currents.
Background of the Invention
[0002] First, the general configuration of a conventional spinning machine will be described
with reference to Figure 7.
[0003] F is a bundle of fibers as an aggregate of short fibers such as slivers which are
accommodated in a can 1. D is a 4-line type draft device composed of a back roller
2, a third roller 3, a second roller 4 around which an apron belt 4a is extended,
and a front roller 5, the draft device D being shown as an example. S is a spinning
member, described later, and 6 is a yarn feeding member composed of a nip roller 6a
and a delivery roller 6b. P is a winding package formed around a bobbin 7 supported
in a bobbin holder (not shown in the drawings). A rotatively driven friction roller
8 abuts against a surface of the winding package P, which is thus rotated. 9 is a
traverse guide of a traverse device (not shown in the drawings).
[0004] The bundle of fibers F drawn out of the can 1 is drafted by the draft device D and
then enters the spinning member S. The bundle of fibers F is thus formed into a yarn
Y. The formed yarn Y is then fed toward the winding package P while being sandwiched
between the nip roller 6a and the delivery roller 6b, which constitute the yarn feeding
member 6. While being traversed by the traverse guide 9, the yarn Y is then wound
into the winding package P, which is rotating while abutting against the friction
roller 8.
[0005] A large number of spinning units each composed of, for example, the draft device
D, the spinning member S, the yarn feeding member 6, and the winding package P, such
as those described above, are arranged in line along a frame (not shown in the drawings)
to constitute a spinning machine.
[0006] Now, with reference to Figures 8 to 11, a description will be given of the spinning
member S, disposed in a conventional spinning machine.
[0007] 10 is a needle holder having a fiber introduction hole 10a into which the bundle
of fibers F drafted by the draft device D and then discharged from the front roller
5 is introduced, the needle holder 10 also having a needle 10b disposed along the
fiber introduction hole 10a and operating as a fiber guide member. The fiber introduction
hole 10a is formed of an introduction passage 10a1 formed substantially like a funnel
and extending substantially parallel to a tangent at a nip point X between a top roller
5a and a bottom roller 5b, both constituting the front roller 5, and an inclined passage
10a2 formed substantially like a cylinder and inclined from the tangent at the nip
point X between the top roller 5a and the bottom roller 5b, both constituting the
front roller 5, the inclined passage 10a2 extending toward the needle 10b. A bent
portion 10a3 is formed at the boundary between the introduction passage 10a1 and the
inclined passage 10a2. Further, an opening 10a1' in the introduction passage 10a1
substantially parallel to the needle 10b, the opening 10a1' being located at the front
roller 5 side, is formed like a horizontally elongate elliptical slot so as to facilitate
introduction of the bundle of fibers F. The introduction passage 10a1 is tapered from
the opening 10a1', formed like a horizontally elongate elliptical slot, toward the
inclined passage 10a2, formed like a cylindrical space portion having a substantially
circular cross section.
[0008] 11 is a nozzle block in which a plurality of air injection holes 11a are formed.
The needle holder 10 and the nozzle block 11 are arranged so that their opposite surfaces
abut against each other. The needle holder 10 is fitted into a mounting hole 12a drilled
in the nozzle housing 12 and located at the front roller 5 side. Further, the nozzle
block 11 is fitted into a mounting hole 12b lying opposite the front roller 5 and
into a mounting hole 13a drilled in a main housing 13. 14 is a plate-like member sandwiched
between the nozzle housing 12 and the main housing 13. The nozzle block 11 is fitted
into a through-hole 14a drilled in the plate member 14. An annular air reservoir 15
and a communication hole 16 are formed in the nozzle housing 12, and the communication
hole 16 is in communication with an annular air reservoir 15. The communication hole
16 is connected to a source of compressed air via a pipe (not shown in the drawings).
Accordingly, compressed air supplied by the source of compressed air enters the air
reservoir 15 through the communication hole 16, and the air is subsequently injected
from the air injection holes 11a, drilled in the nozzle block 11.
[0009] The air injection holes 11a, formed in the nozzle block 11, is drilled in a tangential
direction with respect to an inner peripheral surface 11b of the nozzle block 11.
If the compressed air injected from the air injection holes 11a is whirled counterclockwise
(in the direction of an arrow A1 shown in Figure 9) as viewed from the draft device
D side, a spun yarn with an S twist is generated. On the other hand, if the compressed
air injected from the air injection holes 11a is whirled clockwise as viewed from
the draft device D side, a spun yarn with a Z twist is generated. Consequently, the
nozzle block 11 is replaced depending on the direction of the twist (S or Z twist)
in the desired spun yarn.
[0010] 17 is a rotative or non-rotative hollow guide shaft. The hollow guide shaft 17 is
fitted into a mounting hole 18a drilled in a shaft supporting block 18 installed in
an opening 13b in the main housing 13. 19 is an air chamber formed between the main
housing 13 and the shaft supporting block 18. The air chamber 19 is connected to an
air suction source (not shown in the drawings) via a pipe 13d connected to a suction
hole 13c formed in the main housing 13, the air suction source sucking air at a low
suction pressure. During spinning, the air chamber 19 functions as a space into which
air injected from the air injection holes 11a, drilled in the nozzle block 11, escapes.
The air chamber 19 also functions to suck and remove, for example, floating fibers
generated during spinning.
[0011] Now, with reference mainly to Figures 8 and 9, a description will be given of a process
of generating a yarn using the above described spinning machine.
[0012] The bundle of drafted fibers F fed out of the front roller 5 of the draft device
D enters the fiber introduction hole 10a in the needle holder 10. Subsequently, the
bundle F enters a spinning chamber s1 formed between the nozzle block 11 and a tip
17a of the hollow guide shaft 17. In the spinning chamber s1, a whirling air current
flowing in a predetermined direction is formed by air injected from the air injection
holes 11a, drilled in the nozzle block 11 (in the present embodiment, a whirling air
current flowing counterclockwise as viewed from the front roller 5 is formed as shown
by an arrow A1 in Figure 9). The whirling air current flows downward while whirling
along an outer peripheral surface of the hollow guide shaft 17, and the whirling air
then enters the air chamber 19 and is subsequently discharged from the suction hole
13c via the pipe 13d. Air injected from the air injection holes 11a, drilled in the
nozzle block 11, acts to generate a sucking air current near the opening 10a1' inlet
in the fiber introduction hole 10a in the needle holder 10, which opening is located
at the front roller 5 side. Accordingly, the bundle of drafted fibers F fed out of
the front roller 5 is sucked into the fiber introduction hole 10a.
[0013] The bundle of fibers F exiting the fiber introduction hole 10a of the needle holder
10 is introduced into a hollow passage 17b in the hollow guide shaft 17 while being
wound around the needle 10b, the tip of which is placed close to the inlet of the
hollow passage 17b in the hollow guide shaft 17. Then, the fibers f constituting the
bundle of fibers F exiting the fiber introduction hole 10a in the needle holder 10
have their leading ends entangled with a spun yarn Y' being generated in the hollow
passage 17b in the hollow guide shaft 17 and are thus introduced into the hollow passage
17b in the hollow guide shaft 17. Further, the whirling air current being generated
in the spinning chamber s1 causes the trailing ends f1 of the fibers f to be bent
along an outer peripheral surface of the tip 17a of the hollow guide shaft 17 while
running around the tip 17a of the hollow guide shaft 17 (fibers having their leading
ends inserted into the hollow passage 17b of the hollow guide shaft 17 and having
their trailing ends f1 arranged and bent along the outer peripheral surface of the
tip 17a of the hollow guide shaft 17 will hereinafter be referred to as reversed fibers).
[0014] Moreover, when the trailing ends f1 of the reversed fibers f near the inlet of the
hollow passage 17b of the hollow guide shaft 17 as the spun yarn Y' being generated
moves, the trailing ends f1 of the reversed fibers f are whirled around the spun yarn
Y' being generated and located in the hollow passage 17b of the hollow guide shaft
17. At the same time, the trailing ends f1 are wound around the outer periphery of
the spun yarn Y' to generate a spun yarn Y. In this manner, an actually twisted spun
yarn Y is generated which consists of core fibers composed of the fibers f substantially
straightly introduced into the hollow passage 17b of the hollow guide shaft 17 and
the reversed fibers f wound around the core fibers. The bundle of fibers F is wound
around the needle 10b. Accordingly, even if part of the twist applied by the whirling
air current attempts to propagate toward the front roller 5, the propagation is hindered
by the needle 10b to prevent the bundle of fibers F fed out of the front roller 5
from being twisted.
[0015] The position of the needle 10b-side exhaust port of the inclined passage 10a2, formed
in the needle holder 10, depends on the whirling direction of the whirling air current
generated by air injected against the needle 10b from the air injection holes 11a,
drilled in the nozzle block 13.
[0016] For example, if the whirling air current formed flows counterclockwise as viewed
from the front roller 5 as shown by the arrow A1 in Figure 9 or an arrow A3 in Figure
11, the needle 10b is attached to a position at about 45 degrees from a bottom point
T1 of a substantially circular exhaust port 10a2' of the inclined passage 10a2, forming
the fiber introduction hole 10a, in a counterclockwise direction along the exhaust
port 10a2', in other words, in the whirling direction of the whirling air current.
Attaching the needle 10b to such a position prevents the fibers f constituting the
bundle of fibers F, transferred along the inclined passage 10a2, from being separated
into two directions along the needle 10b. When separated into the two directions along
the needle 10b, the fibers f constituting the bundle of fibers F may be wound around
the needle 10b to preclude the generation of a spun yarn.
[0017] Further, if the whirling current formed flows clockwise as viewed from the front
roller 5, as shown by an arrow A2 in Figure 10, the needle 10b is attached to a position
at about 45 degrees from the bottom point T1 of the substantially circular exhaust
port 10a2' of the inclined passage 10a2, forming the fiber introductin hole 10a, in
a clockwise direction along the exhaust port 10a2', in other words, in the whirling
direction of the whirling air current. Attaching the needle 10b to such a position
prevents the fibers f constituting the bundle of fibers F, transferred along the inclined
passage 10a2, from being separated into the two directions along the needle 10b, as
described above.
[0018] As described above, the whirling direction of the whirling air current is appropriately
switched by applying an S twist or a Z twist to the spun yarn generated. To achieve
this, both needle holder 10 and nozzle block 11 must be replaced.
[0019] The conventional spinning machine described above is disclosed in the Unexamined
Japanese Patent Application Publication (Tokkai) No. 2000-345438
[0020] As described above, if a spun yarn undergoing the desired twist (S or Z twist) is
to be generated, both needle holder 10 and nozzle block 11 must be replaced. Accordingly,
the operation of switching the twist in the spun yarn is inefficient and difficult.
[0021] It is an object of the present invention to solve the problems of the conventional
spinning machine.
Summary of the Invention
[0022] To accomplish this object, the present invention provides a spinning machine in which
a spinning member is disposed, the spinning member having a nozzle block in which
air injection holes are drilled, a hollow guide shaft, a fiber introduction hole opened
at a tip side of the hollow guide shaft, and a fiber guide member that guides fibers
to the tip of the hollow guide shaft, wherein, first, a separation protrusion is formed
in a fiber contact surface of the fiber introduction hole to define a plurality of
passages having different fiber introduction directions with respect to the fiber
guide member, wherein, second, the separation projection is formed so that the plurality
of passages are symmetric with respect to an axis of the fiber guide member, wherein,
third, the fiber introduction hole is formed of an introduction passage at an opening
inlet side and an inclined passage located downstream side of the introduction passage
and extending toward the fiber guide member, and a bent portion is formed at a boundary
between the introduction passage and the inclined passage, the separation projection
being formed downstream side of the bent portion, wherein, fourth, a wall portion
of the separation projection and the inclined passage form a common radius of curvature,
and wherein, fifth, an edge of an exhaust port of the passage which edge is located
at the fiber guide member side is located at a predetermined distance from the axis
of the fiber guide member.
[0023] The separation protrusion is formed in the fiber contact surface of the fiber introduction
hole to define the plurality of passages having the different fiber introduction directions
with respect to the fiber guide member. Consequently, it is unnecessary to replace
a needle holder depending on the whirling direction of a whirling air current generated
in a spinning chamber. This improves the operability of switching of a twist in a
spun yarn.
[0024] The separation projection is formed so that the plurality of passages are symmetric
with respect to the axis of the fiber guide member. Consequently, it is possible to
prevent a variation in the quality of spun yarns such as their strength or uniformity
caused by a variation in the whirling direction of the whirling air current generated
in the spinning chamber.
[0025] The fiber introduction hole is formed of the introduction passage at the opening
inlet side and the inclined passage located downstream side of the introduction passage
and extending toward the fiber guide member. Consequently, a bundle of fibers running
through the fiber introduction hole can have its running speed controlled. This ensures
that the fibers are wound around the fiber guide member. Further, the separation projection
is formed downstream side of the bent portion at the boundary between the introduction
passage and the inclined passage. Consequently, the bundle of fibers running biased
toward one side of the fiber introduction hole, the bias starting in the vicinity
of the bent portion, can be reliably supplied from either direction with respect to
the fiber guide member through the corresponding passage without being divided.
[0026] The wall portion of the separation projection and the inclined passage form the common
radius of curvature. Consequently, the bundle of fibers whirled by the whirling air
current generated in the spinning chamber can run smoothly. This improves the quality
of manufactured spun yarns such as their strength and uniformity.
[0027] The edge of the exhaust port of the passage which edge is located at the fiber guide
member side is located at the predetermined distance from the axis of the fiber guide
member. Consequently, it is possible to more reliably hinder the propagation, toward
the front roller, of a twist applied by the whirling air current to the bundle of
fibers.
Brief Description of the Drawings
[0028]
Figure 1 is a perspective view of a needle holder schematically showing the behavior
of fibers, the needle holder constituting a spinning member of a spinning machine
according to the present invention.
Figure 2 is a partial vertical side sectional view of the spinning member constituting
the spinning machine according to the present invention.
Figure 3 is a front view of the needle holder as viewed from a front roller side,
the needle holder constituting the spinning member of the spinning machine according
to the present invention.
Figure 4 is a rear view of the needle holder as viewed from a side opposite to the
front roller side, the needle holder constituting the spinning member of the spinning
machine according to the present invention.
Figure 5 is a vertical sectional view of the needle holder constituting the spinning
member of the spinning machine according to the present invention.
Figure 6 is a vertical sectional view taken along a line I-I in Figure 2.
Figure 7 is a general perspective view of the spinning machine.
Figure 8 is a vertical sectional view of a spinning member constituting a conventional
spinning machine.
Figure 9 is a partial vertical sectional view of the spinning member constituting
the conventional spinning machine.
Figure 10 is a vertical sectional view taken along a line I-I in Figure 9.
Figure 11 is also a vertical sectional view taken along the line I-I in Figure 9.
Detailed Description of the Preferred Embodiments
[0029] An embodiment of the present invention will be described below. However, the present
invention is not limited to the embodiment. Various changes may be made to the embodiment
without departing from the spirit of the present invention.
[0030] The general configuration of the spinning machine according to the present invention
is the same as that of the spinning machine described with reference to Figure 7.
Accordingly, its detailed description is omitted. Further, the present invention differs
from the above described conventional spinning machine only in the configuration,
operation, and effects of a needle holder. Consequently, with reference to Figures
1 to 6, the description below will focus on the needle holder of the spinning machine
according to the present invention.
[0031] A fiber introduction hole 101 similar to the fiber introduction hole 10a in the needle
holder 10, described above, is also formed in a needle holder 100 according to the
present invention. The fiber introduction hole 101 is formed of an introduction passage
102 that is substantially parallel to a tangent at a nip point X between the top roller
5a and the bottom roller 5b, which constitute the front roller 5, and an inclined
passage 103 inclined with respect to the nip point X between the top roller 5a and
the bottom roller 5b, which constitute the front roller 5, and toward a needle 106
similar to the above described needle 10b and which operates as a fiber guide member.
A bent portion 104 is formed at the boundary between the introduction passage 102
and the inclined passage 103. Further, a lower wall surface 103b inclined substantially
vertically or downward is formed in the middle of a bottom part 103a constituting
a fiber contact surface of the inclined passage 103.
[0032] A cross section of the introduction passage 102 which is perpendicular to the running
direction (the direction of a tangent at the nip point X between the top roller 5a
and the bottom roller 5b, which constitute the front roller 5) of the bundle of fibers
F, the introduction passage 102 forming the fiber introduction hole 101, is formed
like a slot shaped substantially like an ellipse with its larger diameter side extending
in a horizontal direction. A cross section of the inclined passage 103 which is perpendicular
to the running direction of the bundle of fibers F, the inclined passage 103 extending
from the bent portion 104 to the lower wall surface 103b, is also formed substantially
like an ellipse with its larger diameter side extending in the horizontal direction.
[0033] An angular separating projecting portion 105 is projected from a central portion
of the bottom part 103a of the inclined passage 103, located to extend from the bent
portion 104 to the lower wall surface 103b. In the present embodiment, a cross section
of the separating projecting portion 105 which is perpendicular to the running direction
of the bundle of fibers F is formed substantially like an isosceles triangle. Opposite
side walls 105a of the separating projecting portion 105 and the bottom part 103a
of the inclined passage 103 form a common predetermined radius of curvature. The separating
projecting portion 105 defines a plurality of (in this case, two) passages 103S, 103Z
having different fiber introduction directions.
[0034] Immediately below the separating projecting portion 105, projected from the central
portion of the upper end of the lower wall surface 103b, formed in the middle of the
bottom part 103a of the inclined passage 103, in other words, projected from the central
portion of the bottom part 103a of the inclined passage 103, a needle 106 which is
similar to the needle 10b, disposed in the needle holder 10 of the above described
conventional spinning machine, and which operates as a fiber guide member is attached
substantially parallel to the tangent at the nip point X between the top roller 5a
and the bottom roller 5b, which constitute the front roller 5, in other words, substantially
parallel to the introduction passage 102, constituting the fiber introduction hole
101. The needle 106 is attached at a predetermined distance from the edge (in the
present embodiment, the edge bounded by the side walls 105a and the bottom part 103a
and the exhaust port 103d) of the exhaust port 103d of the inclined passage 103. In
the present embodiment, the needle 106 is attached to the needle holder 100 by being
fitted into a hole portion 103c drilled in the lower wall surface 103b. When thus
disposed, the needle 106 hinders a twist applied to the fibers f constituting the
bundle of fibers F from propagating toward the front roller 5. This prevents the twisting
of the bundle of fibers F fed out of the front roller 5.
[0035] As described above, the fiber introduction hole 101 is formed of the introduction
passage 102 and the downward inclined passage 103 via the bent portion 104. Accordingly,
compared to the case in which the fiber introduction hole 101 is straight and is not
formed with the inclined passage 103, it is possible to controllably reduce the running
speed of the bundle of fibers F running through the fiber introduction hole 101. This
ensures that the fibers f constituting the bundle of fibers F can be wound around
the needle 106.
[0036] A description will be given below of the generation of a spun yarn Y using a spinning
machine having the spinning member S in which the needle holder 100 configured as
described above is disposed.
[0037] If a whirling air current flowing clockwise as viewed from the front roller 5 is
formed in the spinning member 1 by air injected from the air injection holes 11a,
drilled in the nozzle block 11, the fibers f constituting the bundle of fibers F located
near the exhaust port 103d of the inclined passage 103 are biased by a clockwise twist
toward one side as shown by an arrow A4 in Figures 3 and 4. Further, the fibers constituting
the bundle of fibers F are wound around the needle 106, attached to the central portion
of the upper end of the lower wall surface 103b, formed in the middle of the bottom
part 103a of the inclined passage 103, in other words, attached to the position (at
a predetermined distance from the exhaust port 103d of the inclined passage 103) of
the lower wall surface 103b which is located immediately below the separating projecting
portion 105 in the figures, being projected from the centrol portion of the bottom
part 103a of the inclined passage 103, via the passage 103S of the inclined passage
103 as shown in Figure 1.
[0038] As described above, the fibers constituting the bundle of fibers F is wound around
the needle 106, attached to the central portion of the upper end of the lower wall
surface 103b, formed in the middle of the bottom part 103a of the inclined passage
103, in other words, attached to the position (at a predetermined distance from the
exhaust port 103d of the inclined passage 103) of the lower wall surface 103b which
is located immediately below the separating projecting portion 105 in the figures,
being projected from the centrol portion of the bottom part 103a of the inclined passage
103. However, the separating projecting portion 105 is projected from the central
portion of the bottom part 103a of the inclined passage 103. Accordingly, the fibers
f constituting the bundle of fibers F running through the inclined passage 103 of
the fiber introduction hole 101 are transferred along the side walls 105a of the separating
projecting portion 105. This reliably prevents the fibers f from being separated into
two directions along the needle 106.
[0039] If a whirling air current flowing counterclockwise as viewed from the front roller
5 is formed in the spinning chamber s1 by air injected from the air injection holes
11a, drilled in the nozzle block 11, the fibers f constituting the bundle of fibers
F located near the exhaust port 103d of the inclined passage 103 are biased by a counterclockwise
twist toward one side as shown by an arrow A5 in Figures 3 and 4. The fibers f constituting
the bundle of fibers F are wound around the needle 106, attached to the central portion
of the upper end of the lower wall surface 103b, formed in the middle of the bottom
part 103a of the inclined passage 103, in other words, attached to the position (at
a predetermined distance from the exhaust port 103d of the inclined passage 103) of
the lower wall surface 103b which is located immediately below the separating projecting
portion 105 in the figures, being projected from the centrol portion of the bottom
part 103a of the inclined passage 103, via passage 103z of the inclined passage 103.
[0040] As described above, the fibers constituting the bundle of fibers F is wound around
the needle 106, attached to the central portion of the upper end of the lower wall
surface 103b, formed in the middle of the bottom part 103a of the inclined passage
103, in other words, attached to the position (at a predetermined distance from the
exhaust port 103d of the inclined passage 103) of the lower wall surface 103b which
is located immediately below the separating projecting portion 105 in the figures,
being projected from the centrol portion of the bottom part 103a of the inclined passage
103. However, the separating projecting portion 105 is projected from the central
portion of the bottom part 103a of the inclined passage 103. Accordingly, the fibers
f constituting the bundle of fibers F running through the inclined passage 103 of
the fiber introduction hole 101 are transferred upward along the side walls 105a of
the separating projecting portion 105. This reliably prevents the fibers f from being
separated into two directions along the needle 106.
[0041] In particular, the separating projecting portion 105 is preferably provided downstream
side of the bent portion 104 of the fiber contact surface (the bottom part 103a of
the inclined passage 103). The reason will described below.
[0042] If the separating projecting portion 105 extends beyond and upstream side of the
bent portion 104, the bundle of fibers F fed from the draft device D is not affected
by twisting enough to run biased toward one side of the fiber introduction hole 101
as shown in Figure 1 while the bundle of fibers F is running upstream side of the
bent portion 104. Thus, the bundle of fibers F runs through the center of the fiber
introduction hole 101 while being divided into two by the separating projecting portion
105. When the bundle of fibers F behaves in this manner, the two bundles of fibers
F obtained by the division are separately supplied to the tip of the hollow guide
shaft 17 while being mounted on the needle 106. As a result, the fibers may be caught
on the needle 106.
[0043] In contrast, in the present embodiment, the separating projecting portion 105 is
provided downstream side of the bent portion 104. Accordingly, as shown in Figure
1, the bundle of fibers F running biased toward one side of the fiber introduction
hole 101 can be guided into one of the passages 103S, 103Z. This ensures that the
bundle of fibers F can be supplied from one direction with respect to the needle 106.
[0044] As described above, the angular separating projecting portion 105 is projected from
the central portion of the bottom part 103 of the inclined passage 103, located to
extend from the bent portion 104 to the lower wall surface 103b. The needle 106 is
attached to the central portion of the upper end of the lower wall surface 103b, formed
in the middle of the bottom part 103a of the inclined passage 103, in other words,
attached to the position (at a predetermined distance from the exhaust port 103d of
the inclined passage 103) of the lower wall surface 103b which is located immediately
below the separating projecting portion 105 in the figures, being projected from the
centrol portion of the bottom part 103a of the inclined passage 103. Accordingly,
the inclined passage 103 is formed into the two passages 103S, 103Z, having different
fiber introduction directions. It is thus unnecessary to replace the needle holder
100 depending on the whirling direction of a whirling air current being generated
in the spinning chamber s1. This improves the operability of switching of a twist
in the spun yarn Y.
[0045] Further, when the separating projecting portion 105 is formed in the center of the
bottom part 103a of the inclined passage 103 so that the angle of the bent portion
104 and the like are equal, the passages 103S, 103Z are formed laterally symmetrically
with respect to the axis of the needle 106. Consequently, even if the whirling direction
of the whirling air current branches to supply the fibers to both passages 103S, 103Z,
the quality of the yarn Y such as its strength or uniformity is prevented from varying
with only the twisting direction reversed.
[0046] Further, as described above, the side walls 105a of the separating projecting portion
105 and the bottom part 103a of the inclined passage 103 form the common predetermined
radius of curvature. Accordingly, the bundle of fibers F being whirled by a clockwise
or counterclockwise whirling air current generated in the spinning chamber s1 can
run smoothly. This improves the quality of the manufactured spun yarn Y such as its
strength or uniformity. The passages 103S, 103Z may be slightly spirally twisted around
the needle 106.
[0047] Moreover, the needle 106 is attached to the central portion of the upper end of the
lower wall surface 103b, formed in the middle of the bottom part 103a of the inclined
passage 103, in other words, attached to the position (at a predetermined distance
from the exhaust port 103d of the inclined passage 103) of the lower wall surface
103b which is located immediately below the separating projecting portion 105 in the
figures, being projected from the centrol portion of the bottom part 103a of the inclined
passage 103. The needle 106 is formed at the predetermined distance from the edge
(in the present embodiment, the edge bounded by the side walls 105a and the bottom
part 103a and the exhaust port 103d) of the exhaust port 103d of the inclined passage
103. Accordingly, the propagation, toward the front roller 5, of a twist applied by
the whirling air current to the bundle of fibers F is hindered not only by the needle
106 but also by the step portion described above. This ensures that the propagation,
toward the front roller 5, of a twist applied to the bundle of fibers F is inhibited.
[0048] The above described embodiment shows the example in which the fiber introduction
hole 101 is formed of the introduction passage 102 substantially parallel to the tangent
at the nip point X between the top roller 5a and the bottom roller 5b, which constitute
the front roller 5, and the inclined passage 103, inclined from the tangent at the
nip point X between the top roller 5a and the bottom roller 5b, which constitute the
front roller 5. However, the whole fiber introduction hole 101 may be formed of the
introduction passage 102 without forming the inclined passage 103.
[0049] Further, the above described embodiment shows the example in which the cross section
of the introduction passage 102 and inclined passage 103 that is perpendicular to
the running direction of the bundle of fibers F, the introduction passage 102 and
inclined passage 103 forming the fiber introduction hole 101, is shaped substantially
like an ellipse with the larger diameter extending in the horizontal direction. However,
the cross section may be formed substantially like a circle. Alternatively, only the
introduction passage 102 may be formed substantially like an ellipse with a larger
diameter extending in the horizontal direction so that the bundle of fibers F discharged
from the front roller 5 is easily introduced into the fiber introduction hole 101.
[0050] Moreover, the above described embodiment shows the example in which the cross section
of the separating projecting portion 105 that is perpendicular to the running direction
of the bundle of fibers F is formed substantially like an isosceles triangle. However,
the present invention is not limited to the cross section shaped substantially like
an isosceles triangle but may use various sectional shape such as a semicircle, a
square, or an angular shape.
[0051] Moreover, the above described embodiment shows the example in which the separating
projecting portion 105 is projected from the central portion of the bottom part 103a
of the inclined passage 103, located to extend from the bent portion 104 to the lower
wall surface 103b. However, if the precisely homogeneous quality of the spun yarn
Y need not be precisely homogeneous regardless of the twisting direction (S or Z twist)
of the manufactured spun yarn Y, the separating projecting portion 105 need not necessarily
be projected from the central portion of the bottom part 103a of the inclined passage
103, located to extend from the bent portion 104 to the lower wall surface 103b. In
this case, the separating projecting portion 105 may be projected from a position
offset from the central portion of the bottom part 103a. However, by projecting the
separating projecting portion 105 from the central portion of the bottom part 103a
of the inclined passage 103, forming the fiber introduction hole 101, it is possible
to prevent a variation in the quality of the spun yarn Y such as its strength or uniformity
caused by a variation in the whirling direction of a whirling air current generated
in the spinning chamber s1. Accordingly, the separating projecting portion 105 is
preferably projected from the central portion of the bottom part 103a of the inclined
passage 103, forming the fiber introduction hole 101.