BACKGROUND OF THE INVENTION
1. Field of the Invention
[0001] The present invention relates to a pot spinning machine.
2. Description of the Related Art
[0002] A pot spinning machine using a cylindrical pot is known as one type of spinning machine.
In a pot spinning machine, a cake is formed by rotating the pot at a predetermined
rotation frequency and guiding yarn drawn out to a predetermined thickness into the
pot through a yarn guide so that the yarn is wound around an inner wall of the pot.
Further, when cake formation is complete, the yarn is cut on the upstream side of
the yarn guide, whereupon a bobbin is inserted into the pot and the yarn is rewound
onto the bobbin from the inner wall of the pot.
[0003] In a conventional pot spinning machine, while a cake C is being formed by winding
yarn 104 around the inner wall of a pot 101, as shown in FIG. 7A, the yarn 104 may
be wound around a yarn guide 105, as shown in FIG. 7B. This phenomenon is known as
"yarn guide wind-up". When the yarn 104 is wound around the yarn guide 105, a wound
part Y of the yarn is formed on the outside of the yarn guide 105. Hence, when the
bobbin is inserted into the pot following formation of the cake and the yarn guide
105 is moved in order to avoid contact between the yarn guide 105 and the bobbin,
as shown in FIG. 7C, the wound part Y of the yarn that is wound around the yarn guide
105 may contact the rotating pot 101. When the wound part Y of the yarn contacts the
pot 101, component damage such as bending of the yarn guide 105 may occur.
[0004] Hence, in a spinning machine described in Patent Document 1 (Japanese Examined Patent
Publication No.
S26-003129), air is ejected from a tip end portion of a yarn guide, and by controlling the airstream
near the tip end portion of the yarn guide, yarn is prevented from being wound up
around the yarn guide.
SUMMARY OF THE INVENTION
[0005] However, even when the airstream near the tip end portion of the yarn guide is controlled,
as in the spinning machine described in Patent Document 1, yarn guide wind-up of the
yarn cannot be completely prevented.
[0006] The present invention has been devised to solve the problem described above, and
an object thereof is to provide a pot spinning machine with which component damage
can be prevented when yarn undergoes yarn guide wind-up.
[0007] To solve the problem described above, a pot spinning machine according to the present
invention includes a pot that has a downward-facing opening and rotates, a yarn guide
that is inserted into the interior of the pot through an attachment hole formed in
an upper portion of the pot in order to guide yarn into the interior of the pot, and
a yarn guide rail that holds the yarn guide and is capable of moving in an elevation
direction, wherein the yarn guide is held by the yarn guide rail via a yarn guide
holder, and a holding force of the yarn guide holder is smaller than a resistance
force that acts on the yarn guide when a wound-up part formed as a result of the yarn
being wound around the yarn guide contacts a non-elevating member.
[0008] Thus, even when the yarn undergoes yarn guide wind-up, force generated when the yarn
wound around the yarn guide contacts another component can be alleviated, and as a
result, component damage can be prevented.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009]
FIG. 1 is a schematic view showing an overall structure of a spindle part of a pot
spinning machine according to an embodiment of the present invention;
FIG. 2 is an enlarged sectional view showing the vicinity of a lower end portion of
a yarn-guide guide of the pot spinning machine shown in FIG. 1;
FIG. 3 is an enlarged sectional view showing a contact location between a yarn guide
holder and a yarn guide of the pot spinning machine shown in FIG. 1;
FIG. 4 is a flowchart showing the flow of an operation performed by the pot spinning
machine shown in FIG. 1;
FIGS. 5A to 5C are views showing a process by which the yarn guide moves relative
to a yarn guide rail so as to withdraw from the yarn guide rail;
FIG. 6 is an enlarged sectional view showing an engagement location between a yarn
guide holder and a yarn guide of a pot spinning machine according to another embodiment
of the present invention; and
FIGS. 7A to 7C are views showing a process by which yarn is wound around a yarn guide
of a conventional pot spinning machine, wherein FIG. 7A is a view showing a state
in which a cake is formed on an inner wall of a pot, FIG. 7B is a view showing a state
in which the yarn undergoes yarn guide wind-up following formation of the cake, and
FIG. 7C is a view showing a state in which the yarn guide, around which the yarn is
wound, has moved upward.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0010] Embodiments of the present invention will be described below on the basis of the
attached figures.
[0011] FIG. 1 is a schematic view showing a spindle part 100 of a pot spinning machine.
Note that a plurality of the spindle part 100 of the pot spinning machine are to be
used when provided in a line on a machine base, not shown in the figure.
[0012] As shown in FIG. 1, the spindle part 100 of the pot spinning machine includes a substantially
cylindrical pot 1. The pot 1 has a downward-facing opening 1a. A bobbin 12 is provided
below the pot 1. The bobbin 12 is capable of ascending and descending in an elevation
direction D, or in other words a vertical direction, and when the bobbin 12 ascends
to a maximum point, the bobbin 12 is housed in the interior of the pot 1.
[0013] A pot support portion 2 is attached to the top of the pot 1. A bearing 2a is provided
in the interior of the pot support portion 2. Further, a yarn-guide guide 8 is provided
in a hollow portion in the interior of the bearing 2a. The yarn-guide guide 8 is provided
so as not to contact the bearing 2a. The yarn-guide guide 8 is formed in a substantially
cylindrical shape, and flanges 8a, 8b are formed respectively on an upper end and
a lower end of the yarn-guide guide 8. As shown in FIG. 2, the flange 8b on the lower
end of the yarn-guide guide 8 is disposed on the lower side of a lower end of the
bearing 2a of the pot support portion 2 and an upper surface 1b of an interior space
of the pot 1. Furthermore, the pot 1 is capable of rotating relative to the yarn-guide
guide 8 via the bearing 2a. Moreover, a yarn guide 5 for guiding yarn 4 into the interior
of the pot 1 is housed in the interior of the yarn-guide guide 8 to be capable of
moving in the elevation direction D. Note that the bearing 2a and the yarn-guide guide
8 are inserted into the interior of the pot 1 through an attachment hole 1c formed
in an upper portion of the pot 1, and therefore the bearing 2a and the yarn-guide
guide 8 are provided between the yarn guide 5 and the pot 1. Furthermore, as shown
in FIG. 1, a lower end of the yarn guide 5 projects into the interior of the pot 1.
A yarn discharge port 5b for discharging the yarn 4 is formed in the lower end of
the yarn guide 5. Moreover, the yarn guide 5 extends so as to project from an upper
end of the pot support portion 2.
[0014] Further, a guide holder rail 15 is provided above the pot support portion 2. A guide
holder 9 is attached to the guide holder rail 15. The flange 8a on the upper end of
the yarn-guide guide 8 is engaged with the guide holder 9 such that the yarn-guide
guide 8 is supported by the guide holder 9.
[0015] Furthermore, an upper end part of the yarn guide 5 is held by a yarn guide rail 6.
A yarn guide holding hole 6a that is penetrated by the yarn guide 5 is formed in the
yarn guide rail 6. Further, as shown in FIG. 3, a gap is present between the yarn
guide 5 and the yarn guide holding hole 6a. An annular yarn guide holder 7 is attached
to a lower side surface of the yarn guide rail 6 so as to extend around the yarn guide
holding hole 6a. The yarn guide holder 7 is formed from resin. The yarn guide holder
7 holds the yarn guide 5 by a holding force P1. The holding force P1 is frictional
force generated between the yarn guide 5 and the yarn guide holder 7. In other words,
the yarn guide rail 6 holds the yarn guide 5 by the holding force P1 via the yarn
guide holder 7. Note that by applying a larger force than the holding force P1 to
the yarn guide 5, the yarn guide 5 can be moved in the elevation direction D relative
to the yarn guide rail 6. Furthermore, as shown in FIG. 1, the yarn guide rail 6 is
capable of moving in the elevation direction D while holding the yarn guide 5. Moreover,
an upper limit of the height of an upper end 5a of the yarn guide 5 when the yarn
guide 5 ascends together with the yarn guide rail 6 is set as an upper limit height
H.
[0016] A drafting device 3 for drawing out the yarn to a predetermined thickness is provided
on the upper side of the yarn guide rail 6. Further, a yarn guide sensor 10 is provided
between the drafting device 3 and the yarn guide rail 6. The yarn guide sensor 10
is a reflective optical sensor. The yarn guide sensor 10 is provided such that an
optical axis 10a thereof is positioned below the upper limit height H of the upper
end 5a of the yarn guide 5.
[0017] Further, a wagon-type bobbin removal device 11 is provided on the machine base on
which the plurality of spindle parts 100 of the pot spinning machine are arranged
so as to be capable of moving in the arrangement direction of the spindle parts 100
of the pot spinning machine. The bobbin removal device 11 is capable of gripping and
removing the bobbin 12 of each of the spindle parts 100 of the pot spinning machine
using a robot arm 11a.
[0018] The bobbin removal device 11 constitutes a bobbin withdrawing mechanism.
[0019] Next, using FIG. 4, an operation of the spindle part 100 of the pot spinning machine
will be described.
[0020] First, as shown in step S1 of FIG. 4, a cake is formed on an inner wall of the pot
1. More specifically, as shown in FIG. 1, as the pot 1 rotates at high speed, the
yarn 4 is guided into the interior of the pot 1 by the yarn guide 5, whereupon the
yarn 4 is discharged through the yarn discharge port 5b in the lower end of the yarn
guide 5. Centrifugal force generated by the rotation of the pot 1 acts on the yarn
4 such that the yarn 4 is pressed against the inner wall of the pot 1, and as a result,
a cake is formed. At this time, the yarn guide rail 6 reciprocates in the elevation
direction D such that the yarn 4 is discharged and the cake is formed as the position
of the yarn discharge port 5b in the lower end of the yarn guide 5 is moved.
[0021] Note that although the pot 1 rotates at high speed, the yarn-guide guide 8 remains
stationary. Here, the yarn-guide guide 8 constitutes a non-rotating portion.
[0022] Next, as shown in step S2 of FIG. 4, following formation of the cake, the yarn guide
rail 6 is raised. Then, as shown in step S3, a determination is made as to whether
or not the yarn guide 5 has been detected by the yarn guide sensor 10. When the yarn
guide sensor 10 detects that the yarn guide 5 is ascending together with the yarn
guide rail 6, this means that the yarn guide 5 is held by the yarn guide rail 6, and
accordingly, it is determined that the yarn 4 is not undergoing yarn guide wind-up.
The operation of the spindle part 100 of the pot spinning machine then advances as
normal to a step (step S4) for rewinding the yarn 4 around the bobbin 12.
[0023] When the yarn guide 5 has not been detected by the yarn guide sensor 10, however,
it is determined in step S3 that the yarn 4 is undergoing yarn guide wind-up. More
specifically, as shown in FIG. 5A, the yarn 4 is wound around the yarn guide 5 such
that a wound part Y of the yarn is formed on the outer periphery of the yarn guide
5. As shown in FIG. 5B, when the yarn guide rail 6 and the yarn guide 5 ascend, the
wound part Y of the yarn contacts the flange 8b on the lower end of the yarn-guide
guide 8 such that a downward resistance force P2 is generated in the yarn guide 5.
When this resistance force P2 exceeds the holding force P1 by which the yarn guide
rail 6 holds the yarn guide 5, the upper end of the yarn guide 5 moves in a downward
direction relative to the yarn guide holding hole 6a of the yarn guide rail 6, as
shown in FIG. 5C, so as to withdraw from the yarn guide holding hole 6a. Hence, when
the yarn 4 is wound around the yarn guide 5, the yarn guide sensor 10 provided on
the upper side of the yarn guide rail 6 cannot detect the presence of the yarn guide
5. In other words, the yarn guide sensor 10 detects that the yarn guide 5 is not held
by the yarn guide rail 6.
[0024] Hence, when the yarn 4 undergoes yarn guide wind-up, the bobbin removal device 11
grips and removes the bobbin 12 using the robot arm 11a, as indicated by step S5 of
FIG. 4.
[0025] Thus, in the pot spinning machine according to this embodiment, the holding force
P1 by which the yarn guide holder 7 provided on the yarn guide rail 6 holds the yarn
guide 5 is smaller than the resistance force P2 exerted on the yarn guide 5 when the
wound part Y formed around the yarn guide 5 contacts a non-elevating member. Accordingly,
when the resistance force P2 acts on the yarn guide 5, the yarn guide 5 then becomes
able to move in the elevation direction D relative to the yarn guide rail 6, thereby
alleviating a force generated when the wound part Y formed around the yarn guide 5
contacts another member. As a result, component damage to the spindle part 100 of
the pot spinning machine is prevented from occurring even when the yarn 4 undergoes
yarn guide wind-up around the yarn guide 5.
[0026] Note that in this embodiment, the pot 1, the bearing 2a, and the yarn-guide guide
8 are non-elevating members.
[0027] Further, the yarn guide 5 is held on the yarn guide rail 6 by the frictional force
generated between the yarn guide 5 and the yarn guide holder 7. As a result, the yarn
guide 5 can be held using a simple structure, and when the resistance force P2 is
exerted on the yarn guide 5 in a predetermined amount or more, the yarn guide 5 can
easily move in the elevation direction D relative to the yarn guide rail 6.
[0028] Furthermore, the yarn guide sensor 10 detects whether or not the yarn guide 5 is
held by the yarn guide rail 6. Hence, by detecting that the yarn guide 5 has moved
in the downward direction relative to the yarn guide rail 6 so as to withdraw from
the yarn guide rail 6, it can be determined that the yarn 4 is undergoing yarn guide
wind-up around the yarn guide 5.
[0029] Moreover, when the yarn 4 undergoes yarn guide wind-up around the yarn guide 5, the
wound part Y of the yarn that is wound around the yarn guide 5 contacts the flange
8b on the lower end of the yarn-guide guide 8 serving as the non-rotating portion.
Hence, even when the wound part Y of the yarn contacts a rotating member such as the
pot 1, the force generated by the contact can be reduced.
[0030] Furthermore, when it is determined that the yarn 4 is undergoing yarn guide wind-up
around the yarn guide 5, the yarn guide 5 is capable of moving in the elevation direction
D relative to the yarn guide rail 6, and therefore contact may occur between the yarn
guide 5 and the bobbin 12. Hence, the bobbin removal device 11 removes the bobbin
12 to prevent contact between the yarn guide 5 and the bobbin 12.
[0031] Note that the yarn guide sensor 10 may display an alarm after detecting that the
yarn guide 5 has moved in the downward direction relative to the yarn guide rail 6
so as to withdraw from the yarn guide rail 6, whereupon the bobbin 12 may be removed
manually. Further, instead of removing the bobbin 12, contact between the yarn guide
5 and the bobbin 12 can be prevented by laying the bobbin 12 down in a horizontal
orientation so that the bobbin 12 is retracted.
[0032] Note that in this embodiment, the yarn guide 5 is held on the yarn guide rail 6 by
the frictional force generated between the yarn guide 5 and the yarn guide holder
7, but the method of holding the yarn guide 5 is not limited thereto.
[0033] For example, as shown in FIG. 6, a recess 13 may be formed in the outer periphery
of the yarn guide 5, and the yarn guide 5 may be held on the yarn guide rail 6 by
engaging the recess 13 with a projection 14 formed on the yarn guide holder 7. Alternatively,
the yarn guide 5 may be held on the yarn guide rail 6 by forming a projection on the
outer periphery of the yarn guide 5 and a recess in the yarn guide holder 7, and engaging
the projection formed on the yarn guide 5 with the recess formed in the yarn guide
holder 7.
[0034] Further, the holding force P1 for holding the yarn guide 5 on the yarn guide rail
6 may be the magnetic force of a magnet or the elastic force of a spring member.
[0035] Furthermore, when the yarn guide holder is a spring member, the yarn guide sensor
may determine whether or not the yarn guide 5 has moved in the downward direction
so as to withdraw from the yarn guide rail 6 by detecting movement of the yarn guide
holder.
[0036] Moreover, the yarn guide sensor 10 is not limited to a reflective optical sensor
and may be a transmissive optical sensor or a contact-type sensor.
[0037] Furthermore, the yarn guide sensor 10 may be attached directly to the vicinity of
the yarn guide holding hole 6a in the yarn guide rail 6.
[0038] Further, instead of providing the flange 8b on the lower end of the yarn-guide guide
8, the wound part Y of the yarn that is wound around the yarn guide 5 may directly
contact the lower end of the yarn-guide guide 8 formed without a flange.
[0039] Furthermore, in a case where the bearing 2a includes an inner race that remains in
a stationary state and an outer race that rotates relative to the inner race, the
inner race of the bearing 2a may serve as the non-rotating portion that is contacted
by the wound part Y of the yarn wound around the yarn guide 5.
[0040] Moreover, even when the yarn-guide guide 8 rotates together with the pot 1, the yarn
guide 5 moves in the downward direction relative to the yarn guide rail 6, and therefore
the force generated by the contact between the wound part Y of the yarn wound around
the yarn guide 5 and the yarn-guide guide 8 is sufficiently alleviated.
[0041] Furthermore, in FIG. 5C, the yarn guide 5 withdraws from the yarn guide rail 6 so
as to be separated therefrom, but the present invention is not limited thereto, and
as long as the yarn guide 5 moves relative to the yarn guide rail 6 in the downward
direction, the force generated by the contact between the wound part Y of the yarn
and the yarn-guide guide 8 is alleviated even if the yarn guide 5 does not withdraw
from the yarn guide rail 6.
[0042] A pot spinning machine includes a pot that has a downward-facing opening and rotates,
a yarn guide that is inserted into the interior of the pot through an attachment hole
formed in an upper portion of the pot in order to guide yarn into the interior of
the pot, and a yarn guide rail that holds the yarn guide and is capable of moving
in an elevation direction, wherein the yarn guide is held by the yarn guide rail via
a yarn guide holder, and a holding force of the yarn guide holder is smaller than
a resistance force that acts on the yarn guide when a wound-up part formed as a result
of the yarn being wound around the yarn guide contacts a non-elevating member. As
a result, force generated when the yarn wound around the yarn guide contacts another
component can be alleviated even when the yarn undergoes yarn guide wind-up.
1. A pot spinning machine comprising:
a pot (1) that has a downward-facing opening (1a) and rotates;
a yarn guide (5) that is inserted into the interior of the pot (1) through an attachment
hole (1c) formed in an upper portion of the pot (1) in order to guide yarn (4) into
the interior of the pot (1); and
a yarn guide rail (6) that holds the yarn guide (5) and is capable of moving in an
elevation direction (D),
the pot spinning machine being characterized in that the yarn guide (5) is held by the yarn guide rail (6) via a yarn guide holder (7),
and
a holding force (P1) of the yarn guide holder (7) is smaller than a resistance force
(P2) that acts on the yarn guide (5) when a wound-up part (Y) formed as a result of
the yarn (4) being wound around the yarn guide (5) contacts a non-elevating member
(8, 2a).
2. The pot spinning machine according to claim 1, wherein the yarn guide rail (6) holds
the yarn guide (5) using frictional force generated between the yarn guide (5) and
the yarn guide holder (7).
3. The pot spinning machine according to claim 1, wherein the yarn guide (5) includes
a recess (13),
the yarn guide holder (7) includes a projection (14) that can be engaged with the
recess (13) formed in the yarn guide (5), and
the yarn guide rail (6) holds the yarn guide (5) by engaging the recess (13) formed
in the yarn guide (5) with the projection (14) formed on the yarn guide holder (7).
4. The pot spinning machine according to any one of claims 1 to 3, further comprising
a yarn guide sensor (10) that detects that the yarn guide (5) is held on the yarn
guide rail (6).
5. The pot spinning machine according to any one of claims 1 to 4, wherein a non-rotating
portion that does not rotate relative to the yarn guide (5) is provided between the
pot (1) that rotates and the yarn guide (5), and
when the yarn guide (5) is moved to an upper side by the yarn guide rail (6) in a
state where the yarn (4) is wound around the yarn guide (5) due to yarn guide wind-up,
the yarn (4) wound around the yarn guide (5) contacts the non-rotating portion.
6. The pot spinning machine according to claim 5, wherein the non-rotating portion (8)
is a yarn-guide guide (8) having a cylindrical shape and provided between the pot
(1) and the yarn guide (5),
the yarn guide (5) is housed in the interior of the yarn-guide guide (8) so as to
be capable of moving in the elevation direction (D),
a flange (8a, 8b) is formed on an end of the yarn-guide guide (8), and
when the yarn guide (5) is moved to the upper side by the yarn guide rail (6) in a
state where the wound part (Y) is formed as a result of the yarn (4) being wound around
the yarn guide (5), the wound part (Y) contacts the flange (8a, 8b) formed on the
yarn-guide guide (8).