YARN STORAGE ROLLER, YARN STORAGE DEVICE, AND YARN WINDING
MACHINE
BACKGROUND OF THE INVENTION
5 1. Field of the Invention
The present invention relates to a yarn storage
roller, a yarn storage device, and a yarn winding machine.
2. Description of the Related Art
10 The yarn winding machine is provided with a yarn
storage roller adapted to store a yarn and the like. The
yarn is wound around an outer circumferential surface of
the yarn storage roller by rotating the yarn storage roller.
The yarn storage roller temporarily stores the yarn, and
15 hence functions as a buffer between a spinning device and
a winding device.
As described in Japanese Unexamined Patent
Publication No. 2013-063839 and Japanese Unexamined Patent
Publication No. 2010-174421, when the yarn breaks at
20 downstream of the yarn storage roller, the yarn remains on
the yarn storage roller. In this case, the yarn storage
roller is reversely rotated to suck and remove the remaining
yarn with a suction device arranged at a base of the yarn
storage roller. As described in Japanese Unexamined
25 Patent Publication No. 2013-159467, there is known a yarn
storage roller made of a resin material which is a
non-metallic material. In such a yarn storage roller, a
base layer having nickel or copper as a main component is
formed on the resin, and a plated layer having chromium as
30 a main component is formed thereon.
The inventors of the present invention have
2/30
considered using a roller main body made of aluminum or
aluminum alloy for a roller main body of the yarn storage
roller. If the roller main body is made of aluminum or
aluminum alloy, a torque for rotating the yarn storage
5 roller can be suppressed low. On the other hand, a
predetermined hardness is required on the surface of the
yarn storage roller. This is because if the hardness of
the surface is low, flaws and the like are easily formed
on the surface, and the yarn on the yarn storage roller may
10 get caught at the flaws and the like.
BRIEF SUMMARY OF THE INVENTION
It is an object of the present invention to provide
a yarn storage roller in which a hardness of a surface is
15 increased even if the roller main body made of aluminum or
aluminum alloy is used, as well as a yarn storage device
and a yarn winding machine including such a yarn storage
roller.
A yarn storage roller of the present invention is a
20 yarn storage roller arranged in a yarn winding machine and
having a surface around which a yarn is wound, the yarn
winding machine including a yarn supplying device adapted
to supply a yarn, and a winding device adapted to wind the
yarn supplied from the yarn supplying device into a package;
25 the yarn storage roller including a roller main body
containing aluminum or aluminum alloy; and a coating layer
formed on the roller main body, wherein a Vickers hardness
(Hv) of the coating layer is greater than or equal to 550.
A yarn storage device according to an aspect of the
30 present invention includes a yarn storage roller having a
coating layer whose Vickers hardness (Hv) is greater than
3/30
or equal to 550; and a yarn hooking member arranged to be
relatively rotatable with respect to the yarn storage
roller, and adapted to rotate at a speed same as or different
from that of the yarn storage roller with the yarn hooked
5 to the yarn hooking member.
A yarn winding machine of the present invention
includes a draft device adapted to draft a fiber bundle;
a spinning device adapted to spin the fiber bundle drafted
by the draft device to spin a yarn; the yarn storage roller
10 adapted to store the yarn spun by the spinning device; and
the winding device adapted to wind the yarn stored on the
yarn storage roller into a package.
BRIEF DESCRIPTION OF THE DRAWINGS
15 FIG. 1 is a front view of a spinning machine according
to one embodiment of the present invention;
FIG. 2 is a side view of a spinning unit of the spinning
machine of FIG. 1;
FIG. 3 is a perspective view illustrating a yarn
20 storage roller in FIG. 2;
FIG. 4A is a cross-sectional view illustrating a
coating layer of the yarn storage roller of the first
embodiment;
FIG. 4B is a cross-sectional view illustrating a
25 coating layer of a yarn storage layer of a second
embodiment;
FIG. 5 is a cross-sectional view illustrating a
coating layer of a yarn storage roller of a third
embodiment;
30 FIG. 6A is a cross-sectional view describing a case
where an impurity exist on the roller main body; and
4/30
FIG. 6B is a cross-sectional view describing a crater
formed when the impurity exist on the roller main body.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
5 Embodiments of the present invention will be
hereinafter described with reference to the drawings. The
same reference numerals are denoted on the same components
in the description of the drawings, and the redundant
description will be omitted.
10 As illustrated in FIG. 1, a spinning machine (yarn
winding machine) 1 includes a plurality of spinning units
2, a yarn joining cart 3, a blower box 4, and a motor box
5 . The plurality of spinning units 2 are arranged in a line,
and each spinning unit 2 produces a yarn Y and winds the
15 yarn Y into a package P. The yarn joining cart 3 performs
a yarn joining operation in the spinning unit 2 in which
the yarn Y is cut. The blower box 4 accommodates a blower
and the like for generating a suction airflow, a whirling
airflow, or the like at each section of the spinning unit
20 2. The motor box 5 accommodates a motor and the like for
supplying power to each section of the spinning unit 2.
In the following description, upstream in a
travelling direction of a sliver S, a fiber bundle F, and
the yarn Y is simply referred to as "upstream in the
25 travelling direction", and downstream in the travelling
direction is simply referred to as "downstream in the
travelling direction". A side where a travelling path of
the yarn Y is located with respect to the yarn joining cart
3 is simply referred to as "front side", and the opposite
30 side is simply referred to as "back side".
As illustrated in FIGS. 1 and 2, each spinning unit
5/30
2 includes a draft device 6, a pneumatic spinning device
(spinning device, yarn supplying device) 7, a yarn
monitoring device 8, a tension sensor 9, a yarn storage
device 50, a waxing device 11, and a winding device 12 in
5 this order from the upstream in the travelling direction.
These devices are directly or indirectly supported by a
machine frame 13 such that the upstream in the travelling
direction is the upper side in a machine height direction
(i.e., downstream in the travelling direction is the lower
10 side in the machine height direction).
The draft device 6 drafts the sliver S including a
natural fiber such as cotton or the like, a synthetic fiber,
or another fiber to produce the fiber bundle F. The draft
device 6 includes a back roller pair 61, a third roller pair
15 62, a middle roller pair 64 provided with an apron belt 63
on each roller, and a front roller pair 65 in this order
from the upstream in the travelling direction. Each roller
pair 61, 62, 64, 65 feeds the sliver S supplied from a can
(not illustrated) from the upstream towards the downstream
20 in the travelling direction while drafting the sliver S.
The pneumatic spinning device 7 applies twists to the
fiber bundle F drafted by the draft device 6 with the
whirling airflow to spin the yarn (spun yarn) Y. More
specifically (although not illustrated), the pneumatic
25 spinning device 7 includes a spinning chamber, a fiber
guiding section, a whirling airflow generating nozzle, and
a hollow guide shaft body. The fiber guiding section is
adapted to guide the fiber bundle F supplied from the draft
device 6 located upstream in the travelling direction to
30 the spinning chamber. The whirling airflow generating
nozzle is arranged at a periphery of a path through which
6 / 30
the fiber bundle F travels, and is adapted to generate the
whirling airflow in the spinning chamber. This whirling
airflow causes a fiber end of the fiber bundle F guided into
the spinning chamber to be reversed and to whirl. The
5 hollow guide shaft body is adapted to guide the spun yarn
Y from the spinning chamber to outside the pneumatic
spinning device 7.
The yarn monitoring device 8 monitors information of
the travelling yarn Y between the pneumatic spinning device
10 7 and the yarn storage device 50, and detects presence or
absence of a yarn defect based on the monitored information.
When the yarn defect is detected, the yarn monitoring device
8 transmits a yarn defect detection signal to a unit
controller 10. The yarn monitoring device 8 detects, for
15 example, thickness abnormality of the yarn Y and/or foreign
substances contained in the yarn Y as the yarn defect. The
tension sensor 9 is adapted to measure tension of the
travelling yarn Y between the pneumatic spinning device 7
and the yarn storage device 50, and transmit a tension
20 measurement signal to the unit controller 10. The waxing
device 11 is adapted to apply wax on the travelling yarn
Y between the yarn storage device 50 and the winding device
12. The unit controller 10 is provided for each spinning
unit 2, and is adapted to control an operation of the
25 spinning unit 2. The unit controller 10 may be arranged
for each group of the plurality of spinning units 2.
The yarn storage device 50 is adapted to store the
travelling yarn Y between the pneumatic spinning device 7
and the winding device 12. The yarn storage device 50 has
30 a function of stably pulling out the yarn Y from the
pneumatic spinning device 7, a function of preventing the
7/30
yarn Y from slackening by retaining the yarn Y fed from the
pneumatic spinning device 7 during the yarn joining
operation by the yarn joining cart 3 or the like, and a
function of preventing fluctuation in the tension of the
5 yarn Y from the winding device 12 from being transmitted
towards the pneumatic spinning device 7 by adjusting the
tension of the yarn Y from the winding device 12. If the
spinning unit 2 includes a delivery roller and a nip roller,
the delivery roller and the nip roller have the function
10 of pulling out the yarn Y from the pneumatic spinning device
7.
The winding device 12 is adapted to wind the yarn Y
spun by the pneumatic spinning device 7 to form the package
P. The winding device 12 includes a cradle arm 21, a winding
15 drum 22, and a traverse device 23. The cradle arm 21 is
swingably supported by a supporting shaft 24, and brings
a surface of a rotatably supported bobbin B or a surface
of the rotatably supported package P (i.e., the bobbin B
around which the yarn Y is wound) into contact with the
20 surface of the winding drum 22 at an appropriate pressure.
The winding drum 22 is driven by an electric motor (not
illustrated) provided in each spinning unit 2 to rotate the
bobbin B or the package P making contact with the winding
drum 22. The traverse device 23 is driven by a shaft 25
25 shared among the plurality of spinning units 2, and
traverses the yarn Y over a prescribed width with respect
to the rotating bobbin B or the rotating package P.
The yarn joining cart 3 travels to the spinning unit
2 in which the yarn Y is disconnected to perform the yarn
30 joining operation in the relevant spinning unit 2 . The yarn
joining cart 3 includes a splicer 26, a suction pipe 27,
8/30
and a suction mouth 28. The suction pipe 27 is swingably
supported by a supporting shaft 31, is adapted to suck and
catch the yarn end of the yarn Y from the pneumatic spinning
device 7 to guide the yarn end to the splicer 26. The
5 suction mouth 28 is swingably supported by a supporting
shaft 32, and is adapted to suck and catch the yarn end of
the yarn Y from the winding device 12 to guide the yarn end
to the splicer 26. The splicer 26 joins the guided yarn
ends .
10 Next, the configuration of the yarn storage device
50 will be described. As illustrated in FIGS. 2 and 3, the
yarn storage device 50 includes a yarn storage roller 51,
a yarn hooking member 54, an electric motor 55, and a stored
yarn amount sensor (reflective sensor) 56.
15 The yarn storage roller 51 is fixed to a drive shaft
of the electric motor 55 to be rotated by the electric motor
55. The yarn storage roller 51 includes a yarn storage
section 51a. The yarn storage section 51a is a
substantially cylindrical portion around which the yarn Y
20 is wound, and is slightly tapered towards the distal end
(downstream). A recess 51b having a shape depressed with
respect to the yarn storage section 51a is formed at a
central portion of the yarn storage section 51a. For
example, when an operator cuts the yarn Y wound around the
25 yarn storage roller 51 with a tool such as a pair of scissors,
a cutter, or the like, the distal end of the tool is placed
in the recess 51b.
The yarn hooking member 54 is arranged at a downstream
end of the yarn storage roller 51. The yarn hooking member
30 54 is configured to be able to hook (guide) the yarn Y. The
yarn hooking member 54 is arranged to be relatively
9/30
rotatable with the yarn storage roller 51. When the yarn
hooking member 54 is rotated together with the yarn storage
roller 51 with the yarn Y hooked to the yarn hooking member,
the yarn Y is wound around the surface of the yarn storage
5 roller 51. Specifically, the yarn Y is hooked to the yarn
hooking member 54 at the start (including restart) of
storing of the yarn Y on the yarn storage roller 51. When
the yarn hooking member 54 is integrally rotated with the
yarn storage roller 51 at the same speed with the yarn Y
10 hooked to the yarn hooking member 54, the yarn Y is wound
around the surface of the yarn storage roller 51.
In addition to the introducing function of winding
the yarn Y around the yarn storage roller 51 at the start
of storing of the yarn Y as described above, the yarn hooking
15 member 54 also has an unwinding tension applying function
of applying an appropriate (stable) tension on the yarn Y
unwound (pulled out) from the yarn storage roller 51.
Specifically, for example, when the load with respect to
the yarn hooking member 54 is smaller than or equal to a
20 predetermined value (when the yarn Y unwound while being
hooked to the yarn hooking member 54 is about to slacken) ,
the yarn hooking member 54 rotates (integrally rotates)
integrally with the yarn storage roller 51 so that the yarn
Y is wound around the surface of the yarn storage roller
25 51. When the load with respect to the yarn hooking member
54 exceeds a predetermined value, the yarn hooking member
54 rotates (relatively rotates) at a speed different from
that of the yarn storage roller 51 so that the yarn Y is
unwound from the yarn storage roller 51. In other words,
30 the yarn Y is unwound from the yarn storage roller 51 when
the tension of the yarn Y located downstream of the yarn
10 / 30
storage roller 51 is increased, and the unwinding of the
yarn Y is stopped when the tension of the yarn Y located
downstream of the yarn storage roller 51 is reduced. The
yarn hooking member 54 thus can apply an appropriate tension
5 on the yarn Y unwound from the yarn storage roller 51. The
yarn hooking member 54 can absorb the fluctuation in the
tension of the yarn Y between the yarn storage roller 51
(yarn storage device 50) and the winding device 12.
The yarn Y is continuously wound around the yarn
10 storage roller 51 at a constant speed (entrance speed) from
the yarn supplying side, which is the upstream, and the yarn
Y is pulled out at the speed (exit speed) same as or
substantially the same as the winding speed of the winding
device 12 while applying tension by the yarn hooking member
15 54 from the winding side, which is the downstream. The
entrance speed is set to coincide with the rotation speed
of the yarn storage roller 51, and to be the speed same as
the spinning speed or the speed slightly faster than the
spinning speed. The exit speed changes by the influence
20 of the winding speed of the winding device 12 and the
influence of the rotation speed of the yarn hooking member
54. The position (unwinding position) where the yarn Y
comes out from the yarn storage roller 51 also changes. If
the exit speed is greater than the entrance speed, the
25 stored amount of the yarn wound around the yarn storage
roller 51 is reduced. On the contrary, if the exit speed
is smaller than the entrance speed, the stored amount of
the yarn wound around the yarn storage roller 51 is
increased. The direction of the yarn Y unwound from the
30 yarn storage roller 51 is not the circumferential direction
of the yarn storage roller 51, but is the direction along
11 / 30
the axial direction.
The yarn storage roller 51 and the yarn hooking member
54 may be rotatably driven by one common motor, or may be
independently rotatably driven by different motors. A
5 rotational axis of the yarn storage roller 51 and a
rotational axis of the yarn hooking member 54 have the same
axis line. If the motors of the yarn hooking member 54 and
the yarn storage roller 51 are common, the yarn hooking
member 54 is configured to generate a resistance torque
10 against the relative rotation of the yarn storage roller
51 by a predetermined relative rotation resistance means.
According to such a resistance torque, the yarn hooking
member 54 can rotate integrally with the yarn storage roller
51 following the rotation of the yarn storage roller 51.
15 When a force greater than the resistance torque is applied
to the yarn hooking member 54, the yarn hooking member 54
can relatively rotate with respect to the yarn storage
roller 51. That is, if the tension of the yarn Y located
downstream of the yarn storage device 50 is greater than
20 the resistance torque, the yarn hooking member 54
relatively rotates with respect to the yarn storage roller
51. The tension applied on the yarn Y unwound from the yarn
storage roller 51 can be determined by the magnitude of the
resistance torque. The relative rotation resistance means
25 is, for example, a magnetic means, an electromagnetic means
by an electromagnet, or a mechanical means by a frictional
force.
The stored yarn amount sensor 56 is a light reflective
sensor adapted to detect presence or absence of the yarn
30 Y on the yarn storage roller 51 in a non-contacting manner,
and is arranged on the back of the yarn storage roller 51
12 / 30
so as to face the yarn storage roller 51. When the stored
amount of the yarn Y wound around the yarn storage roller
51 reaches a lower limit amount, the stored yarn amount
sensor 56 transmits a stored-amount lower limit detection
5 signal to the unit controller 10.
As illustrated in FIG. 4A, the yarn storage roller
51 of the first embodiment includes a roller main body 52,
and a coating layer 57A formed on a surface 52a of the roller
main body 52. The roller main body 52 is made of aluminum.
10 The roller main body 52 is formed by die cast molding, for
example.
The coating layer 57A includes an intermediate layer
58A arranged on the surface 52a of the roller main body 52,
and a surface layer 59A arranged on the intermediate layer
15 58A. The surface layer 59A is made of a material different
from that of the intermediate layer 58A. More specifically,
the intermediate layer 58A is formed by the copper plating.
The surface layer 59A includes a non-electrolytic nickel
layer 59a formed on the intermediate layer 58A, and a hard
20 chromium plated layer 59b formed on the non-electrolytic
nickel layer 59a.
The thickness of the coating layer 57A having such
a three-layer structure is smaller than 15 urn. For example,
the thickness of the intermediate layer 58A is smaller than
25 5 am, the thickness of the non-electrolytic nickel layer
59a is smaller than 5 am, and the thickness of the hard
chromium plated layer 59b is smaller than 5 jam. The
thickness of the coating layer 57A may be smaller than 25
am.
30 In describing the method for forming the coating
layer 57A, the surface 52a of the roller main body 52 is
13 / 30
subjected to a mirror surface processing prior to forming
the coating layer 57A. Each layer constituting the coating
layer 57A can be formed through a known method. Since the
surface 52a of the roller main body 52 is subjected to the
5 mirror surface processing, a surface 57a of the formed
coating layer 57A becomes a mirror surface.
In the yarn storage roller 51 of the first embodiment,
the Vickers hardness (Hv) of the coating layer 57A is
greater than or equal to 550. The Vickers hardness (Hv)
10 of the coating layer 57A can be adjusted by adjusting the
thickness of the surface layer 59A, and the like. The
Vickers hardness (Hv) of the coating layer 57A may be
greater than or equal to 700, or may be greater than or equal
to 800. The Vickers hardness (Hv) of the coating layer 57A
15 may be greater than or equal to 1000. The Vickers hardness
(Hv) is smaller than or equal to 7000. Rationally
(realistically), the Vickers hardness (Hv) is preferably
smaller than or equal to 1500.
Since the roller main body 52 of the yarn storage
20 roller 51 is made of aluminum and the aluminum is light
weight, the torque of the electric motor 55 when rotating
the yarn storage roller 51 can be reduced. The Vickers
hardness (Hv) of the coating layer 57A formed on the roller
main body 52 is greater than or equal to 550, whereby the
25 hardness of the surface 57a is increased, and flaws and the
like are less likely to be formed on the surface 57a.
For example, even when the yarn Y wound around the
yarn storage section 51a is cut with a tool such as a pair
of scissors, a cutter, or the like, flaws are less likely
30 to be formed on the surface 57a of the coating layer 57A
by the tool. The Vickers hardness (Hv) of the tool such
14 / 30
as the pair of scissors, the cutter, or the like is, for
example, about 500 or smaller than 500. The Vickers
hardness (Hv) of the coating layer 57A is greater than the
Vickers hardness (Hv) of the tool. The damage of the
5 surface 57a is prevented because the distal end of the tool
enters into the recess 51b, for example.
If the Vickers hardness (Hv) of the coating layer 57A
is greater than or equal to 700, the hardness of the surface
57a becomes higher. For example, even if a cutting tool
10 (cutter or the like) having a Vickers hardness (Hv) of about
550 is used, flaws are less likely to be formed on the surface
57a of the coating layer 57A.
The hardness of the surface 57a is increased by
forming the coating layer 57A with a plurality of layers
15 including the intermediate layer 58A and the surface layer
5 9A.
The intermediate layer 58A is formed by the copper
plating. Since copper is soft, even if impurities and the
like exist or irregularities are formed on the surface 52a
20 of the roller main body 52, the impurities and/or
irregularities can be covered and hidden by the copper
plating. As a result, the intermediate layer 58A can be
made uniform, and furthermore, the surface of the surface
layer 59A can be made uniform.
25 The surface layer 59A includes the non-electrolytic
nickel layer 59a, so that the hard chromium plated layer
59b can be easily formed thereon. The surface of the
surface layer 59A can be made uniform by forming the
intermediate layer 58A by the copper plating, and
30 furthermore, the hardness of the surface 57a can be
increased by arranging the hard chromium plated layer 59b
15 / 30
in the surface layer 59A. In the surface layer 59A, it is
also effective to arrange another intermediate layer
between the non-electrolytic nickel layer 59a and the hard
chromium plated layer 59b.
5 When detecting whether or not the yarn Y exists on
the yarn storage roller 51 by the stored yarn amount sensor
56, the reflection efficiency of the light is improved since
the surface of the coating layer 57A is a mirror surface.
The detection accuracy of the stored yarn amount sensor 56
10 is thus enhanced. The output in the stored yarn amount
sensor 56 can be reduced. With the arrangement of the hard
chromium plated layer 59b, the surface 57a of the coating
layer 57A becomes a whitish color. The reflection
efficiency of the light at the surface 57a is improved by
15 the whitish color of the surface 57a.
As described above, the roller main body 52 made of
aluminum is formed by die cast molding. As illustrated in
FIG. 6A, a fine impurity X may exist on the surface (outer
circumferential surface) 52a of the roller main body 52.
20 When forming a coating layer 157 on the surface 52a, a crater
100 is likely to be formed at the periphery of the impurity
X, as illustrated in FIG. 6B. Conventionally, the coating
layer 157 is required to be formed thick to increase the
strength of the coating layer 157. In particular, if the
25 roller main body 52 is made of aluminum, the coating layer
157 is required to be formed greater than or equal to a
prescribed thickness.
If the coating layer 157 is formed thick in a state
where the crater 100 is formed, the diameter R of the crater
30 100 becomes large, as illustrated in FIG. 6B. For example,
if the thickness of the coating layer 157 is 25 \xm, the
16 / 30
diameter of the crater is between 1 mm and 2 mm. If the
diameter R of the crater 100 is large, for example, the yarn
Y on the yarn storage roller 51 may get caught at the surface.
In the yarn storage roller 51 of the present
5 embodiment, the coating layer 57A formed on the surface 52a
of the roller main body 52 is formed thin, i.e., smaller
than 25 jum, so that the diameter of the crater can be made
small even if the crater is formed.
The thermal processing need not be performed when
10 forming the coating layer 57A, and hence the shape of the
roller main body 52 can be maintained.
According to the spinning machine 1 of the present
embodiment, the hardness of the yarn storage roller 51 is
increased so that flaws and the like are less likely to be
15 formed on the surface (yarn storage section 51a or the like)
of the yarn storage roller 51. Therefore, the yarn Y is
prevented from getting caught at the surface of the yarn
storage roller 51. Since the roller main body 52 is made
of aluminum, the torque of the electric motor 55 when
20 rotating the yarn storage roller 51 can be reduced.
Next, a second embodiment will be described. As
illustrated in FIG. 4B, the yarn storage roller 51 of the
second embodiment includes the roller main body 52, and a
coating layer 57B formed on the surface 52a of the roller
25 main body 52. The roller main body 52 is made of aluminum.
The roller main body 52 is formed by die cast molding, for
example.
The coating layer 57B includes an intermediate layer
58B arranged on the surface 52a of the roller main body 52,
30 and a surface layer 59B arranged on the intermediate layer
58B. The surface layer 59B is made of a material different
17 / 30
from that of the intermediate layer 58B. More specifically,
the intermediate layer 58B is formed by the
non-electrolytic nickel plating. The surface layer 59B is
formed by the hard chromium plating.
5 The thickness of the coating layer 57B having such
a two-layer structure is, for example, about 10 \xm. For
example, the thickness of the intermediate layer 58B is
about 5 jum, and the thickness of the surface layer 59B is
about 5 \xm. The thickness of the coating layer 57B may be
10 smaller than 25 |j,m.
In the yarn storage roller 51 of the second embodiment,
the Vickers hardness (Hv) of the intermediate layer 58B is
500. The Vickers hardness (Hv) of the surface layer 59B
is 1000. The Vickers hardness (Hv) of the coating layer
15 57B is, for example, 1000. The Vickers hardness (Hv) of
the coating layer 57B can be adjusted by adjusting the
thickness of the surface layer 59A, and the like. The
Vickers hardness (Hv) of the coating ' layer 57B may be
greater than or equal to 550, may be greater than or equal
20 to 700, or may be greater than or equal to 800. The Vickers
hardness (Hv) is smaller than or equal to 7000. Rationally
(realistically), the Vickers hardness (Hv) is preferably
smaller than or equal to 1500.
Even when such a coating layer 57B is arranged, the
25 effects similar to those of the coating layer 57A described
above can be obtained. For example, flaws and the like are
less likely to be formed since the hardness of the surface
57a is increased. The detection accuracy of the stored yarn
amount sensor 56 is enhanced since the surface 57a is a
30 mirror surface.
With the arrangement of the intermediate layer 58B
18 / 30
made of the non-electrolytic nickel, the surface layer 59B
formed by the hard chromium plating can be easily formed.
The hardness of the surface 57a is increased since the
hardness of the hard chromium plating is high. The coating
5 layer 57B does not use copper, and thus the yarn storage
roller 51 having high hardness can be manufactured
relatively inexpensively.
Next, a third embodiment will be described. As
illustrated in FIG. 5, the yarn storage roller 51 of the
10 third embodiment includes the roller main body 52, and a
coating layer 57C formed on the surface 52a of the roller
main body 52. The roller main body 52 is made of aluminum.
The roller main body 52 is formed by die cast molding, for
example.
15 The coating layer 57C is formed by thermal processing.
The coating layer 57C is made of a non-electrolytic nickel
layer, for example. The thickness of the coating layer 57C
is, for example, 25 urn. The thickness of the coating layer
57C may be smaller than 20 urn, or may be smaller than 15
20 |im.
In the coating layer 57C performed with the thermal
processing, a non-electrolytic nickel (Ni-P) coated layer
is precipitated as an amorphous (noncrystalline) alloy of
nickel and phosphorous. The coated layer is crystallized
25 by the baking process to increase the hardness. In other
words, the hardness is increased by crystallizing the
coated layer of nickel and phosphorous.
In the yarn storage roller 51 of the third embodiment,
the Vickers hardness (Hv) of the coating layer 57C is
30 greater than or equal to 550. The Vickers hardness (Hv)
of the coating layer 57C can be adjusted by adjusting the
19 / 30
thickness of the coating layer 57C and/or the temperature,
time, or the like of the thermal processing. The Vickers
hardness (Hv) of the coating layer 57C may be greater than
or equal to 700, or may be greater than or equal to 800.
5 The Vickers hardness (Hv) of the coating layer 57C may be
greater than or equal to 1000. The Vickers hardness (Hv)
is smaller than or equal to 7000. Rationally
(realistically), the Vickers hardness (Hv) is preferably
smaller than or equal to 1200.
10 The embodiments of the present invention have been
described above, but the present invention is not limited
to the embodiments described above.
For example, in the coating layer 57B having the
two-layer structure illustrated in FIG. 4B, the
15 intermediate layer 58B may be formed by the copper plating,
and the surface layer 59B may be formed by the nickel
chromium plating. In this case as well, the Vickers
hardness (Hv) of the coating layer may be set to the same
extent as the embodiments described above. The surface of
20 the surface layer 59B can be made uniform by forming the
intermediate layer 58B by the copper plating, and
furthermore, the hardness of the surface is increased by
forming the surface layer 59B by the nickel chromium
plating.
25 The roller main body 52 is not limited to being made
of aluminum, and may be made of aluminum alloy. In other
words, the roller main body 52 may contain aluminum alloy.
The yarn storage roller 51 or the yarn storage device
50 may be arranged in an automatic winder (yarn winding
30 machine). The automatic winder includes the yarn
supplying device adapted to supply the yarn wound around
20 / 30
the yarn supplying bobbin, and the winding device adapted
to wind the yarn supplied from the yarn supplying device
into the package. In other words, the yarn storage roller
or the yarn storage device of the present invention is
5 arranged in the yarn winding machine including the yarn
supplying device adapted to supply the yarn, and the winding
device adapted to wind the yarn supplied from the yarn
supplying device into the package. If the yarn winding
machine is the spinning machine, the spinning device
10 corresponds to the yarn supplying device. The yarn storage
roller or the yarn storage device is arranged between the
yarn supplying device and the winding device. The yarn
supplied from the yarn supplying device is temporarily
stored by being wound around the surface of the yarn storage
15 roller, and the yarn unwound from the yarn storage roller
is wound into the package by the winding device.
A yarn storage roller of the present invention is a
yarn storage roller arranged in a yarn winding machine and
having a surface around which a yarn is wound, the yarn
20 winding machine including a yarn supplying device adapted
to supply a yarn, and a winding device adapted to wind the
yarn supplied from the yarn supplying device into a package;
the yarn storage roller including a roller main body
containing aluminum or aluminum alloy; and a coating layer
25 formed on the roller main body, wherein a Vickers hardness
(Hv) of the coating layer is greater than or egual to 550.
The Vickers hardness (Hv) is smaller than or equal to 7000.
In other words, the roller main body is made of aluminum
or aluminum alloy. The roller main body is not limited to
30 being made of aluminum having a purity of 100% or aluminum
alloy. The Vickers hardness (Hv) is a numerical value
21 / 30
obtained through a test method defined in JIS Z 2244, 7725
(Japanese Industrial Standards corresponding to ISO 6507-1
to 4). The Vickers hardness (Hv) was measured by a Micro
Vickers Hardness Tester. The load used for measuring the
5 Vickers hardness (Hv) was "0.01 kgf".
Since aluminum and aluminum alloy are light weight,
the torque when rotating the yarn storage roller can be
suppressed low. The Vickers hardness (Hv) of the coating
layer formed on the roller main body is greater than or equal
10 to 550, whereby the hardness of the surface is increased,
and flaws and the like are less likely to be formed on the
surface.
The Vickers hardness (Hv) of the coating layer is
greater than or equal to 700. In this case, the hardness
15 of the surface is further increased. The Vickers hardness
(Hv) is preferably smaller than or equal to 1500 or smaller
than or equal to 1200.
The coating layer includes an intermediate layer
arranged on the roller main body, and a surface layer
20 arranged on the intermediate layer and made of a material
different from that of the intermediate layer. In this case,
the coating layer has a two-layer structure, so that the
hardness of the surface is increased.
For example, the intermediate layer is made of
25 non-electrolytic nickel, and the surface layer is formed
by hard chromium plating. With the arrangement of the
intermediate layer made of non-electrolytic nickel, the
surface layer formed by the hard chromium plating can be
easily formed. Since the hardness of the hard chromium
30 plating is high, the hardness of the surface is increased.
For example, the intermediate layer is formed by
22 / 30
copper plating. Since copper is soft, even if impurities
and the like exist or irregularities are formed on the
surface of the roller main body, the impurities and/ or the
irregularities can be covered and hidden by the copper
5 plating. As a result, the intermediate layer can be made
uniform, and furthermore, the surface of the surface layer
can be made uniform.
The surface layer includes a non-electrolytic nickel
layer and a hard chromium plated layer formed on the
10 non-electrolytic nickel layer. The surface layer includes
the non-electrolytic nickel layer, so that the hard
chromium plated layer can be easily formed thereon. The
surface of the surface layer can be made uniform by forming
the intermediate layer by the copper plating, and
15 furthermore, the hardness of the surface can be increased
by arranging the hard chromium plated layer in the surface
layer.
For example, the surface layer is formed by the nickel
chromium plating. In this case, the surface of the surface
20 layer can be made uniform by forming the intermediate layer
by the copper plating, and furthermore, the hardness of the
surface is increased by forming the surface layer by the
nickel chromium plating.
The surface of the coating layer is a mirror surface.
25 When detecting whether or not the yarn exists on the yarn
storage roller by a reflective sensor, reflection
efficiency of the light is improved since the surface of
the coating layer is a mirror surface. Detection accuracy
of the reflective sensor is thus enhanced. Furthermore,
30 output in the reflective sensor can be reduced.
For example, the coating layer is formed by thermal
23 / 30
processing. In this case, the hardness of the coating layer
is increased by performing the thermal processing.
The thickness of the coating layer is smaller than
25 \im. If an impurity and the like exist on the surface
5 of the roller main body, a crater is likely to be formed
at a periphery of the impurity when the coating layer is
formed on the surface. The diameter of the crater can be
reduced by making the coating layer formed on the surface
of the roller main body thin, i.e., smaller than 25 jam.
10 A yarn storage device of the present invention
includes a reflective sensor adapted to detect a yarn on
the coating layer. According to such a yarn storage device,
the coating layer is arranged so that the reflection
efficiency of the light at the surface of the yarn storage
15 roller is improved. The detection accuracy of the
reflective sensor is thus enhanced. Furthermore, the
output in the reflective sensor can be reduced.
The yarn storage device of the present invention
further includes a yarn hooking member arranged to be
20 relatively rotatable with respect to the yarn storage
roller, and adapted to rotate at a speed same as or different
from that of the yarn storage roller with the yarn hooked
to the yarn hooking member. Since the yarn storage device
includes the yarn hooking member, a travelling speed
25 (entrance speed) of the yarn entering the yarn storage
roller is constant, whereas a travelling speed (exit speed)
of the yarn exiting from the yarn storage roller arid a
position (unwinding position) where the yarn exits change.
As a result, the yarn slides in a circumferential direction
30 of the yarn storage roller on the surface of the yarn storage
roller, and the yarn storage roller is in an easily wearable
24 / 30
state. However, since the hardness of the surface of the
yarn storage roller is increased, flaws and the like are
less likely to be formed on the surface of the yarn storage
roller.
5 A yarn winding machine of the present invention
includes a draft device adapted to draft a fiber bundle;
a spinning device adapted to spin the fiber bundle drafted
by the draft device to spin a yarn; the yarn storage roller
adapted to store the yarn spun by the spinning device; and
10 the winding device adapted to wind the yarn stored on the
yarn storage roller into a package. According to such a
yarn winding machine, since the hardness of the surface of
the yarn storage roller is increased, flaws and the like
are less likely to be formed on the surface of the yarn
15 storage roller. Therefore, the yarn is prevented from
getting caught at the surface of the yarn storage roller.
Furthermore, since the roller main body contains aluminum
or aluminum alloy, the torque when rotating the yarn storage
roller can be reduced.
20 According to the present invention, the hardness of
the surface of the yarn storage roller is increased even
if the roller main body made of aluminum or aluminum alloy
is used, and flaws and the like are less likely to be formed
on the surface.

We claim:
1. A yarn storage roller arranged in a yarn winding
machine and having a surface around which a yarn is wound,
5 the yarn winding machine including a yarn supplying device
adapted to supply a yarn, and a winding device adapted to
wind the yarn supplied from the yarn supplying device into
a package, the yarn storage roller comprising:
a roller main body containing aluminum or aluminum
10 alloy; and
a coating layer formed on the roller main body,
wherein a Vickers hardness (Hv) of the coating layer
is greater than or equal to 550.
15 2. The yarn storage roller according to claim 1,
wherein the Vickers hardness (Hv) of the coating layer is
greater than or equal to 700.
3. The yarn storage roller according to claim 1 or
20 2, wherein
the coating layer includes
an intermediate layer arranged on the roller main
body, and
a surface layer arranged on the intermediate layer
25 and made of a material different from that of the
intermediate layer.
4. The yarn storage roller according to claim 3,
wherein the intermediate layer is made of
30 non-electrolytic nickel, and
the surface layer is formed by hard chromium plating.
26 / 30
5. The yarn storage roller according to claim 3,
wherein the intermediate layer is formed by copper plating.
5 6. The yarn storage roller according to claim 5,
wherein the surface layer includes a non-electrolytic
nickel layer, and a hard chromium plated layer formed on
the non-electrolytic nickel layer.
10 7. The yarn storage roller according to claim 5,
wherein the surface layer is formed by nickel chromium
plating.
8 . The yarn storage roller according to any one of
15 claims 1 to 7, wherein a surface of the coating layer is
a mirror surface.
9. The yarn storage roller according to claim 1 or
2, wherein the coating layer is formed by thermal
20 processing.
10. The yarn storage roller according to any one of
claims 1 to 9, wherein a thickness of the coating layer is
smaller than 25 um.
11. A yarn storage device comprising:
the yarn storage roller according to any one of claims
1 to 10; and
a reflective sensor adapted to detect a yarn on the
30 coating layer of the yarn storage roller.
27 / 30
12. The yarn storage device according to claim 11,
further comprising:
a yarn hooking member arranged to be relatively
rotatable with respect to the yarn storage roller, and
5 adapted to rotate at a speed same as or different from that
of the yarn storage roller with the yarn hooked to the yarn
hooking member.
13. A yarn storage device comprising:
the yarn storage roller having a surface around which
a yarn is wound; and
a yarn hooking member arranged to be relatively
rotatable with respect to the yarn storage roller, and
adapted to rotate at a speed same as or different from that
of the yarn storage roller with the yarn hooked to the yarn
hooking member,
the yarn storage roller including:
a roller main body made of aluminum or aluminum
alloy; and
a coating layer formed on the roller main body,
wherein a Vickers hardness (Hv) of the coating layer
is greater than or equal to 550.
14. A yarn winding machine comprising:
25 a draft device adapted to draft a fiber bundle;
a spinning device adapted to spin the fiber bundle
drafted by the draft device to spin a yarn;
the yarn storage roller according to any one of claims
1 to 10 adapted to store the yarn spun by the spinning device;
30 and
the winding device adapted to wind the yarn stored
on the yarn storage roller into a package.