SPINNING MACHINE AND SPINNING METHOD
TECHNICAL FIELD
[0001] The present invention relates to a spinning machine and a spinning method.
BACKGROUND ART
[0002] Conventionally, a spinning machine including a yarn supply device, a winding device, and a yarn accumulation device is known. PTL 1 discloses a spinning frame which is the spinning machine of this type.
[0003] In the spinning machine of PTL 1, a yarn accumulation device includes a yarn accumulation roller. Yarn can be temporarily accumulated by winding the yarn around an outer circumferential surface of the yarn accumulation roller. A suction device is provided downstream of the yarn accumulation roller. When a yarn breakage occurs downstream of the yarn accumulation device, the yarn remaining on the yarn accumulation roller is sucked by the suction device and removed.
PRIOR-ART DOCUMENTS PATENT DOCUMENTS
[0004] PTL 1: Japanese Unexamined Patent Application Publication No. 2014-125349
SUMMARY OF THE INVENTION
PROBLEMS TO BE SOLVED BY THE INVENTION
[0005] However, the configuration of PTL 1 above only discloses a configuration for removing the yarn remaining on the yarn accumulation roller when a yarn breakage occurs downstream of the yarn accumulation device.

[0006] It is an object of the present invention to make it possible to properly treat, with a simple configuration, yarn remaining on a yarn accumulation roller after the yarn is disconnected upstream of the yarn accumulation device in a yam travel direction.
MEANS FOR SOLVING THE PROBLEMS AND EFFECTS THEREOF
[0007] In a first aspect of the present invention, a spinning machine having the following configuration is provided. That is, the spinning machine includes a yarn supply device, a winding device, and a yam accumulation device. The yam supply device is capable of supplying yarn. The winding device winds the yarn supplied from the yarn supply device to form a package. The yarn accumulation device is disposed in the middle of a yarn travel path formed between the yarn supply device and the winding device. The yarn accumulation device has a yarn accumulation roller and a yarn acting part. The yam accumulation roller winds and accumulates the yam supplied from the yarn supply device. The yarn acting part restrains a yarn end of the yarn on a package side with respect to an upstream end area of the yarn accumulation roller by acting air on the yarn end of the yarn on the package side when the yarn is disconnected upstream of the yarn accumulation device in a yam travel direction. After the yarn is disconnected, while the yarn acting part acts air on the yarn, the package is rotated in a forward rotation direction, which is a direction to wind the yarn by the winding device, so as to unwind the yarn remaining on the yarn accumulation roller from the yarn accumulation roller. Rotation of the package in the forward rotation direction is stopped at timing after the yarn end of the yarn on the package side leaves the yam accumulation roller and before the yarn end is wound onto the package.
[0008] In this specification, a case in which the yarn acting part restrains the yam end of the yarn on the package side includes a case in which the yam acting part restrains the part

where the yarn completely ends, and a case in which the yam acting part restrains the
vicinity of the part where the yarn ends.
[0009] As a result, after the yarn is disconnected upstream of the yarn accumulation
device in the yam travel direction, the yam on the package side can be properly treated with
a simple configuration. By using air, the yarn end of the yarn on the package side can be
reliably restrained.
[0010] It is preferable that the spinning machine is configured as follows. That is, the
spinning machine includes a switching valve and a control device. The switching valve
switches between generating and stopping an air flow in the yarn acting part. The control
device controls the switching valve.
[0011] This makes it possible to generate the air flow only when necessary in the yarn
acting part. Therefore, energy saving is realized.
[0012] It is preferable that the spinning machine is configured as follows. That is, the
yarn acting part is a suction device. The suction device includes a suction opening facing
the yarn accumulation roller, and the yarn end of the yarn remaining on the yarn
accumulation roller is sucked at the suction opening.
[0013] By sucking the yarn end of the yam remaining on the yarn accumulation roller,
the behavior of the yarn can be stabilized. As a result, the yam end does not become
entangled with the yarn so that the yarn remaining on the yarn accumulation roller can be
easily unwound.
[0014] It is preferable that the spinning machine is configured as follows. That is, the
yarn accumulation device includes a yam introduction part disposed upstream of the most
upstream part where the yarn is wound around an outer circumferential surface of the yarn
accumulation roller. The yarn supplied from the yarn supply device is led to the most
upstream part of the yam accumulation roller via the yarn introduction part. The suction

opening is arranged to face the yarn introduction part.
[0015] This ensures that the yarn end of the yarn remaining on the yam accumulation
roller is sucked by the suction opening of the suction device.
[0016] It is preferable that the spinning machine is configured as follows. That is, the
yarn accumulation roller accumulates the yarn by rotating in a forward rotation direction
which is a direction in which the yarn from upstream is wound. When the yarn is
disconnected upstream of the yarn accumulation device in the yam travel direction, rotation
of each of the package and the yarn accumulation roller in the forward rotation direction is
stopped. After each of the package and the yam accumulation roller has stopped rotating
in the forward rotation direction, the yarn accumulation roller rotates in a backward rotation
direction.
[0017] As a result, the yarn end of the yarn remaining on the yam accumulation roller is
unwound upstream by the rotation of the yarn accumulation roller in the backward rotation
direction. Therefore, the yam end can be more reliably sucked by the suction opening of
the suction device.
[0018] In the spinning machine, it is preferable that the yarn accumulation roller is
rotated in the forward rotation direction after the yam accumulation roller has been rotated
in the backward rotation direction.
[0019] As a result, the yam accumulation roller is rotated in the forward rotation
direction while the yarn is being sucked into the suction opening. Therefore, the yarn
accumulation roller generates a winding and tightening action on the yarn that is continuous
between the package and the yarn accumulation roller. This causes the yam remaining on
the yarn accumulation roller to be lined up in an orderly manner. Therefore, the yarn
remaining on the yarn accumulation roller can be unwound smoothly from the yarn
accumulation roller.

[0020] It is preferable that the spinning machine is configured as follows. That is,
compared to an amount of rotation when the yarn accumulation roller is rotated in the
backward rotation direction, an amount of rotation when the yarn accumulation roller is
rotated in the forward rotation direction after the yarn accumulation roller has been rotated
in the backward rotation direction is smaller.
[0021] This prevents the yarn end, which is sucked into the suction opening of the
suction device when the yarn accumulation roller is rotated in the backward rotation
direction, from exiting the suction opening when the yarn accumulation roller is rotated in
the forward rotation direction. Accordingly, the restraining action by the suction device
can be continued.
[0022] In the spinning machine, the yarn acting part can be an ejection device that ejects
air in vicinity of the yarn accumulation roller.
[0023] By ejecting air by the ejection device, the behavior of the relevant part of the yarn
can be substantially stabilized.
[0024] It is preferable that the spinning machine is configured as follows. That is, the
yarn accumulation device includes a yarn engaging member and a yarn release member.
The yarn engaging member rotates relative to the yarn accumulation roller. A yarn
unwound from the yarn accumulation roller is engaged with the yarn engaging member.
The yarn release member performs a yarn release operation to release the yarn travel path
from the yarn engaging member at first timing, which is timing later than timing at which
the yarn end of the yarn on the package side leaves the yarn accumulation roller.
[0025] As a result, when the yarn end of the yarn on the package side leaves the yarn
accumulation roller, even if the yarn end is entangled with the yarn engaging member, this
yarn end can be released from the yarn engaging member by the yarn release member.
[0026] It is preferable that the spinning machine is configured as follows. That is, the

yarn release member is configured to perform the yarn release operation also at second
timing different from the first timing. A first movement amount of the yarn release
member with respect to the yarn release operation performed at the first timing is different
from a second movement amount of the yam release member with respect to the yarn
release operation performed at the second timing.
[0027] As a result, when the yarn end of the yam on the package side leaves the yarn
accumulation roller, even if the yam end is entangled with the yarn engaging member, the
yarn end can be reliably released from the yarn engaging member by the yarn release
operation different from the others.
[0028] In the spinning machine, it is preferable that the yam supply device, the winding
device, and the yarn accumulation device are provided in each of the plurality of spinning
units.
[0029] This makes it easier to use the yam supply device, the winding device, and the
yarn accumulation device.
[0030] In the spinning machine, it is preferable that each of the plurality of the spinning
units includes a drive unit for the winding device.
[0031] This allows control to independently drive and stop the winding device for each
spinning unit.
[0032] It is preferable that the spinning machine is configured as follows. That is, in
each of the plurality of the spinning units, the yam accumulation device includes a yarn
engaging member and a yarn release member. The yarn engaging member rotates relative
to the yarn accumulation roller. The yarn unwound from the yarn accumulation roller is
engaged with the yarn engaging member. The yarn release member performs a yarn
release operation to release the yarn travel path from the yarn engaging member later than
timing at which the yam end of the yam on the package side leaves the yarn accumulation

roller. Each of the plurality of the spinning units includes a drive unit for the yarn release member.
[0033] As a result, unlike the conventional configuration, the yarn release lever can be controlled to operate independently for each spinning unit.
[0034] In a second aspect of the present invention, a spinning method as follows is provided. That is, the spinning method is performed in a spinning machine including a yarn supply device, a winding device, and a yarn accumulation device. The yarn supply device is capable of supplying yarn. The winding device winds the yarn supplied from the yarn supply device to form a package. The yarn accumulation device is disposed in a yarn travel path formed between the yarn supply device and the winding device. The yarn accumulation device has a yarn accumulation roller and a yarn acting part. The yarn accumulation roller winds and accumulates the yarn supplied from the yarn supply device. The yarn acting part restrains a yarn end of the yarn on a package side with respect to an upstream end area of the yarn accumulation roller by acting air on the yarn end of the yarn on the package side when the yarn is disconnected upstream of the yarn accumulation device in a yarn travel direction. After the yarn is disconnected, while the yarn acting part acts air on the yarn, the package is rotated in a forward rotation direction, which is a direction to wind the yarn by the winding device, so as to unwind the yarn remaining on the yarn accumulation roller from the yarn accumulation roller. Rotation of the package in the forward rotation direction is stopped at timing after the yarn end of the yarn on the package side leaves the yarn accumulation roller and before the yarn end is wound onto the package.
[0035] As a result, the yarn on the package side can be properly treated after the yarn is disconnected upstream of the yarn accumulation device in the yarn travel direction.

BRIEF DESCRIPTION OF THE DRAWINGS
[0036] FIG. 1 is a side view of a spinning unit provided in a spinning machine according
to one embodiment of the present invention.
FIG. 2 is a control block diagram of the spinning unit.
FIG. 3 is a diagram showing the positional relationship between a yarn accumulation roller and a suction device in a yarn accumulation device.
FIG. 4 is a diagram showing a rotation state of a package and the yarn accumulation roller.
FIG. 5 is a diagram illustrating a detection device and a catching device.
EMBODFMENT FOR CARRYFNG OUT THE INVENTION
[0037] A spinning machine in accordance with an embodiment of the present invention will now be described with reference to FIGS. 1 and 2. In the following description, "upstream" and "downstream" refer to upstream and downstream, respectively, in the traveling direction (yarn travel direction) of the yarn (specifically, a sliver 3, a fiber bundle 5, and spun yarn 7).
[0038] The spinning machine includes at least one spinning unit 1 and a machine control device. The machine control device is not shown in the drawings. The machine control device manages one or more spinning units 1. The spinning unit 1 sends the fiber bundle 5 towards downstream in the yarn travel direction by a drafting device 11, spins the fiber bundle 5 sent from the drafting device 11 by a spinning device 13 to produce the spun yarn 7, and winds the spun yarn 7 by a winding device 21 to form a package 9. In FIG. 5, a cylindrical-shaped package 9 is illustrated. The spinning machine may be configured so that the spun yarn 7 is wound onto a conical-shaped package 9. [0039] As shown in FIG. 1, one spinning unit 1 is equipped with the drafting device 11,

the spinning device 13, a yam monitoring device 15, a yarn accumulation device 17, a yam joining device 19, and the winding device 21. The drafting device 11, the spinning device 13, the yarn monitoring device 15, the yarn accumulation device 17, the yarn joining device 19, and the winding device 21 are arranged in order from the upstream to the downstream in the yarn travel direction.
[0040] As shown in FIG. 2, the aforementioned devices and the like included in the spinning unit 1 are controlled by a unit controller (control device) 25 provided in the spinning unit 1. At least one of the plurality of devices provided in the spinning unit 1 may be controlled by the machine control device. One unit controller may be provided for each predetermined number of the spinning units 1.
[0041] The drafting device 11 generates the fiber bundle 5 by stretching (drafting) the sliver 3 supplied from a can (not shown in drawings) or the like. The drafting device 11 nips the sliver 3 between a plurality of drafting rollers and a plurality of opposing rollers facing the plurality of drafting rollers, while rotating the drafting rollers in the drafting direction to convey the sliver 3 downstream. As a result, the sliver 3 is stretched until it reaches a predetermined fiber quantity (or thickness), and the fiber bundle 5 is generated. [0042] The drafting device 11 includes a back roller 31, a third roller 33, a middle roller 35, and a front roller 37 as a plurality of drafting rollers. These rollers 31,33,35, and 37 are arranged in order from the upstream to the downstream. The middle rollers 35 have rubber apron belts 39 which are wound around them. Each of the drafting rollers is rotatably driven at a predetermined rotation speed.
[0043] The spinning device 13 is provided downstream of the front roller 37 of the drafting device 11. The spinning device 13 applies twists to the fiber bundle 5 supplied from the drafting device 11 to produce the spun yam (yam) 7. In the present embodiment, an air type spinning device that uses a swirling air flow to provide twists to the fiber bundle

5 is adopted as the spinning device 13.
[0044] In the spinning unit 1 (spinning machine), the drafting device 11 and the spinning device 13 configure a yarn supply device 23 capable of supplying the spun yarn 7. The spun yarn 7 generated by the yarn supply device 23 travels from the yarn supply device 23 to the winding device 21. A yarn path (yarn travel path) along which the spun yarn 7 travels is formed between the yarn supply device 23 and the winding device 21. [0045] The yarn monitoring device 15 is provided downstream of the spinning device 13. The yarn monitoring device 15 monitors the presence or absence and quality (thickness and/or presence or absence of foreign matter, etc.) of the spun yarn 7. In the yarn monitoring device 15, the yarn is monitored in a non-contact manner by a transmission type optical sensor. When the yarn monitoring device 15 detects a yarn defect (e.g., a point where the thickness of the spun yarn 7 is abnormal) in the spun yarn 7, the yarn monitoring device 15 sends a yarn defect detection signal to the unit controller 25. [0046] When the unit controller 25 receives the yarn defect detection signal, the unit controller 25 cuts the spun yarn 7 by stopping spinning by the spinning device 13. That is, the spun yarn 7 is disconnected. When the unit controller 25 stops spinning in the spinning device 13, the unit controller 25 stops the drafting operation by the drafting device 11. Further, the unit controller 25 stops a winding operation by the winding device 21 and a pull-out operation by the yarn accumulation device 17 at the same time as the cutting of the spun yarn 7 or at the timing when a predetermined time has elapsed after the spun yarn 7 is cut.
[0047] The yarn monitoring device 15 is not limited to a transmission type optical sensor, but may, for example, use a capacitive sensor to monitor the presence or absence and quality of the spun yarn 7. Instead of a configuration in which the spun yarn 7 is cut by stopping the spinning, a configuration in which the spun yarn 7 is cut by a cutting device provided

in the vicinity of the yarn monitoring device 15 may be adopted.
[0048] The yarn accumulation device 17 is provided downstream of the yarn monitoring device 15 (i.e., downstream of the spinning device 13). The yarn accumulation device 17 is disposed in a yarn path (yarn travel path) formed between the yarn supply device 23 and the winding device 21. The yarn accumulation device 17 includes a yarn accumulation roller 41, a yarn accumulation motor 43, a flyer (yarn engaging member) 45, a yarn detection sensor 47, a suction device (yarn acting part) 49, and a yarn release lever (yarn release member) 51.
[0049] The yarn accumulation roller 41 is capable of winding and accumulating the spun yarn 7 supplied from the yarn supply device 23. The spun yarn 7 is accumulated in a state where it is wound around an outer circumferential surface of the yarn accumulation roller 41. The yarn accumulation roller 41 is rotated in a forward rotation direction or a backward rotation direction by the yarn accumulation motor 43. In the present embodiment, since a pair of delivery rollers that are known are not provided between the spinning device 13 and the yarn accumulation device 17, the yarn accumulation device 17 performs a pull-out operation to pull out the spun yarn 7 from the spinning device 13. However, the pair of delivery rollers may be provided between the spinning device 13 and the yarn accumulation device 17.
[0050] The yarn accumulation motor 43 is configured as an electric motor capable of rotating forward and backward. The yarn accumulation motor 43 rotates in the forward rotation direction to rotate the yarn accumulation roller 41 in the forward rotation direction. The yarn accumulation motor 43 rotates in the backward rotation direction to rotate the yarn accumulation roller 41 in the backward rotation direction. During a normal spinning performance in the spinning unit 1, the yarn accumulation motor 43 rotates the yarn accumulation roller 41 in the forward rotation direction so that the pull-out operation is

performed.
[0051] The flyer 45 is attached to a downstream end (distal end part) of the yarn accumulation roller 41. The flyer 45 is capable of contacting the spun yam 7 pulled out from the yarn accumulation roller 41. The flyer 45 is supported so as to be rotatable relative to the yarn accumulation roller 41. A permanent magnet is attached to either the flyer 45 or the yam accumulation roller 41, and a magnetic hysteresis material is attached to the other. These magnetic means generate a torque that resists rotation of the flyer 45 relative to the yarn accumulation roller 41. Accordingly, with the spun yarn 7 being engaged with the flyer 45, only when a force that overcomes the above torque is applied to the flyer 45 (i.e., when more than a predetermined tension is applied to the spun yam 7), the flyer 45 rotates relative to the yam accumulation roller 41 and the spun yam 7 wound on the yam accumulation roller 41 can be unwound. On the other hand, if the flyer 45 is not subjected to a force that overcomes this torque, the yarn accumulation roller 41 and the flyer 45 rotate together and the spun yam 7 is accumulated by the yarn accumulation roller 41.
[0052] In this manner, the yarn accumulation device 17 operates to unwind the spun yarn 7 when the tension of the downstream spun yarn 7 increases, and to stop unwinding the spun yarn 7 when the tension of the downstream spun yam 7 decreases (the spun yarn 7 is about to slacken). As a result, the yarn accumulation device 17 can eliminate the slackening of the spun yam 7 and provide an appropriate tension to the spun yarn 7. In addition, the flyer 45 operates to absorb the fluctuation of the tension applied to the spun yarn 7 between the yam accumulation device 17 and the winding device 21 as described above. Therefore, the fluctuation of the tension can be prevented from affecting the spun yarn 7 between the spinning device 13 and the yarn accumulation device 17. [0053] The yarn accumulation device 17 may not be equipped with than these magnetic

means and may be equipped with, for example, electromagnets instead of a permanent magnet. The yarn accumulation device 17 may not be equipped with magnetic means and may be provided with a motor that rotationally drives the flyer 45.
[0054] The yarn detection sensor 47 is a sensor for detecting a yarn accumulation amount on the yarn accumulation roller 41. The yarn detection sensor 47 is provided to detect the spun yarn 7 at a predetermined position of the yarn accumulation roller 41. By detecting the presence or absence of the spun yarn 7 at the predetermined position, the yarn detection sensor can detect whether the yarn accumulation amount is more than the predetermined amount. When the spun yarn 7 is being wound onto the package 9, the unit controller 25 controls the rotation speed of a winding drum 63 of the winding device 21 according to the detection result of the yarn detection sensor 47 to adjust the yarn accumulation amount on the yarn accumulation roller 41 to be an amount (value) within a predetermined range. [0055] The suction device 49 is disposed at a side of the yarn accumulation roller 41 in a direction intersecting the axial direction of the yarn accumulation roller 41. The suction device 49 is provided with a hollow pipe 73. The suction device 49 is connected to a suction source 75 as a negative pressure source and is capable of generating a suction air flow in the pipe 73. The suction device 49 generates a suction air flow in the vicinity of the yarn accumulation roller 41 when the spun yarn 7 is disconnected upstream of the yarn accumulation device 17 in the yarn travel direction (between the yarn supply device 23 and the yarn accumulation device 17). As a result, the suction device 49 can suck and catch the part of the spun yarn 7 on the package 9 side that is upstream of the yarn accumulation roller 41.
[0056] The yarn release lever 51 is disposed in the vicinity of the yarn accumulation roller 41. The yarn release lever 51 can perform a yarn release operation to release the spun yarn 7 (yarn travel path) from the flyer 45. The yarn release lever 51 is movable so

that it can be moved between a standby position and a yarn release position. In FIG. 1, the state in which the yam release lever 51 is in the standby position is shown, and the direction of movement of the yarn release lever 51 when it moves from the standby position to the yarn release position is indicated by an arrow. In the process of moving the yarn release lever 51 from the standby position to the yarn release position, the yarn release lever 51 passes through a space downstream of the yarn accumulation roller 41. At this time, if the spun yarn 7 is engaged with the flyer 45, the yarn release lever 51 acts on the spun yarn 7, and this spun yarn 7 is released from the flyer 45.
[0057] In the present embodiment, the yarn release lever 51 is configured as a single spinning-unit drive type. That is, the yarn release lever 51 is provided in each spinning unit 1, and a single drive unit (such as a motor or an air cylinder) is provided for each yarn release lever 51. Therefore, the yarn release lever 51 can operate independently of the yarn release levers 51 of other spinning units 1.
[0058] At a position located downstream of the yarn accumulation roller 41, a guide (guide member) 55 is provided to guide the spun yarn 7 to be wound onto the package 9. The guide 55 can restrict the path of the spun yarn 7 at a position downstream of the yarn accumulation roller 41. The guide 55 is, for example, a U-shaped part or partially cut-out round-shaped part formed on a plate-like member fixedly provided for the spinning unit 1. [0059] The yarn joining device 19 is provided downstream of the guide 55 (i.e., downstream of the yarn accumulation device 17). When the spun yarn 7 is disconnected between the yarn supply device 23 and the winding device 21 in the yarn travel direction, the yarn joining device 19 performs a yam joining process to join the spun yarn 7 from the yarn supply device 23 and the spun yarn 7 from the package 9. In this embodiment, the yarn joining device 19 is a splicer device that twists the yam ends together by a swirling air flow generated by air. For example, a mechanical knotter or the like can be adopted as the

yarn joining device 19 instead of the splicer device.
[0060] A guide device 57 is provided in the spinning unit 1. The guide device 57 guides the spun yarn 7 from the yarn supply device 23 to the yam joining device 19 when the spun yarn 7 is disconnected upstream of the yam accumulation device 17. The guide device 57 is rotatably supported at one end in the longitudinal direction thereof, and can be rotated in the vertical direction. The guide device 57 is provided with a hollow member and is connected to the suction source 75. The guide device 57 can generate a suction air flow at a suction opening 59 formed at the other end in the longitudinal direction thereof. The guide device 57 can be rotated downwardly to catch, with the suction opening 59, the yam end of the spun yarn 7 from the yam supply device 23. After the guide device 57 catches the yam end of the spun yarn 7 from the yarn supply device 23, it can be rotated upwardly to guide this yarn end to the yarn joining device 19.
[0061] The guide device 57 guides the yarn end of the spun yarn 7 from the yarn supply device 23 to the yarn joining device 19. The spun yam 7 from the package 9 is disposed in a guided state with respect to the yarn joining device 19 by being caught by a catching device 83, as described below. In this state, the yarn joining device 19 is driven to perform the yam joining process so that the spun yam 7 from the yarn supply device 23 and the spun yarn 7 from the package 9 are connected. As a result, even when the spun yarn 7 is disconnected upstream of the yam accumulation device 17, the spinning unit 1 can resume the stopped spinning, perform the yarn joining process, and wind the spun yarn 7 from the yarn supply device 23 onto the package 9 again.
[0062] The winding device 21 is provided downstream of the yarn accumulation device 17 (downstream of the yarn joining device 19 in this embodiment). The winding device 21 winds the spun yarn 7 supplied from the yam supply device 23 to form the package 9. In this embodiment, in the height direction of the spinning unit 1, the winding device 21 is

located at a higher position than an upstream end of the drafting device 11. Thus, the spinning unit 1 has a layout in which the yarn path is provided to go from the bottom to the top. The winding device 21 includes a cradle arm 61 and the winding drum 63. [0063] The cradle arm 61 can rotatably support a winding tube 67 for winding the spun yarn 7. The cradle arm 61 is rotatable with its base part as a rotation center. As a result, the winding device 21 can appropriately continue winding the spun yarn 7 even if the diameter of the package 9 increases as the spun yarn 7 is wound onto the winding tube 67. [0064] The winding drum 63 rotates in contact with the outer circumference surface of the winding tube 67 or the package 9 with the winding drum drive motor (not shown in drawings) being controlled by the unit controller 25. The outer circumferential surface of the winding drum 63 is formed with a traverse groove which is not shown in the drawings. The traverse groove allows the spun yarn 7 to be traversed within a predetermined width. As a result, the winding device 21 can wind the spun yarn 7 onto the winding tube 67 while traversing the yarn to form the package 9.
[0065] In this embodiment, the winding device 21 is configured as a single spinning-unit drive type. That is, the winding device 21 in each spinning unit 1 is configured to have a single drive unit (winding drum drive motor) which rotates the winding drum 63 and thus rotates the package 9. The winding device 21 can change the rotational operation of the package 9 independently of the winding devices 21 of the other spinning units 1. [0066] Instead of the winding device 21 having a winding drum 63 with the traverse groove, the winding device 21 may have a known configuration with a winding drum without the traverse groove and a traverse guide that is provided independently of the winding drum and reciprocates.
[0067] Next, referring to FIGS. 3 and 4, the processing of the spun yarn 7 on the package 9 side, which is performed after the spun yarn 7 is disconnected between the yarn supply

device 23 and the yarn accumulation device 17, will be described.
[0068] When spinning by the spinning unit 1 is normally performed, the package 9 in the winding device 21 and the yam accumulation roller 41 in the yam accumulation device 17 are rotated in a predetermined direction, respectively. In the following description, the predetermined direction in which the package 9 rotates at this time may be referred to as forward rotation direction, and the predetermined direction in which the yarn accumulation roller 41 rotates may be referred to as forward rotation direction.
[0069] In the spinning unit 1, when the spun yarn 7 is supplied from the yam supply device 23 and the package 9 is rotated in the forward rotation direction, the spun yarn 7 may be cut according to the monitoring results of the yarn monitoring device 15 as described above. In this case, the spun yarn 7 is disconnected between the yarn supply device 23 and the yam accumulation device 17 in the yam travel direction. In the present embodiment, the spun yarn 7 is cut by stopping the feeding operation of the yarn supply device 23. Then, the pull-out operation of the yarn accumulation device 17 and the winding operation of the winding device 21 are stopped immediately or after a predetermined time.
[0070] At the time when the spun yarn 7 is disconnected, a yam end 7t of the spun yarn 7 on the package 9 side is located between the yarn supply device 23 and the yam accumulation device 17, as shown by the chain line in FIG. 1. In this embodiment, the yarn end 7t is caught in advance by the suction device 49 of the yam accumulation device 17 (see the reference numeral 7c in FIG. 3), and in this state, the winding operation by the winding device 21 is performed at a slower speed than that before the spun yam 7 is disconnected, so that the spun yarn 7 remaining on the yarn accumulation roller 41 is unwound from the yarn accumulation roller 41 to the winding device 21 side. The operation of the suction device 49 in this case will be described later.

[0071] The unwinding of the spun yarn 7 from the yarn accumulation roller 41 progresses, and eventually the unwinding of the spun yarn 7 from the yarn accumulation roller 41 is completed. When the spun yarn 7 is completely unwound from the yarn accumulation roller 41, its end leaves the yarn accumulation roller 41 and is caught by the catching device 83 immediately thereafter. The change in the yarn path accompanying the catching of the spun yarn 7 by the catching device 83 is detected by a detection device 81. Details of the catching device 83 and the detection device 81 will be described later. [0072] When the detection device 81 no longer detects the spun yarn 7, the unit controller 25 stops the rotation of the package 9 in the forward rotation direction by the winding device 21. As a result, the yarn end 7t of the spun yarn 7 on the package 9 side can be positioned downstream of the yarn accumulation device 17 and upstream of the winding device 21.
[0073] As a result, after the spun yarn 7 is disconnected between the yarn supply device 23 and the yarn accumulation device 17 in the yarn travel direction, the spun yarn 7 on the package 9 side can be appropriately treated with a simple configuration. In this embodiment, a yarn defect contained in the spun yarn 7 on the package 9 side can be removed from the spun yarn 7 by the catching device 83. The position at which the yarn end 7t of the spun yarn 7 on the package 9 side is caught by the catching device 83 is not particularly limited. The position can be any position between the yarn accumulation device 17 and the winding device 21 in the yarn travel direction.
[0074] Next, the suction device 49 will be described in detail. When the spun yarn 7 is disconnected between the yarn accumulation device 17 and the yarn supply device 23, the drafting operation of the drafting device 11 is immediately stopped. In conjunction with the stopping of the drafting operation, the pull-out operation of the yarn accumulation device 17 and the winding operation of the winding device 21 are stopped immediately or

after a predetermined time. Accordingly, the yarn end 7t of the spun yarn 7 on the package 9 side is positioned upstream of the yarn accumulation roller 41, and the spun yarn 7 on the package 9 side stops in a state where the spun yarn 7 is connected between the package 9 and the yarn accumulation device 17. Then, rotation of the package 9 in the forward rotation direction by the winding device 21 is resumed at a lower speed than before the disconnection, and the spun yarn 7 is unwound from the yarn accumulation roller 41 to the downstream side. In the process of this unwinding operation, the yarn end 7t located upstream of the yarn accumulation roller 41 is sucked and caught by the suction device 49. [0075] Specifically, the unit controller 25 generates a suction air flow in the suction device 49 to cause the suction device 49 to suck and catch, with a suction opening 71, the yarn end 7t positioned upstream of the yarn accumulation roller 41. As a result, the spun yarn 7 is restrained with respect to an upstream end area of the yarn accumulation roller 41 so that the path of the spun yarn 7 slightly upstream of the yarn accumulation roller 41 does not change until the spun yarn 7 remaining on the yarn accumulation roller 41 is completely unwound towards the downstream. In other words, the suction device 49 restricts the behavior of the spun yarn 7 so that the yarn end 7t of the spun yarn 7 does not become free and the position of the spun yarn 7 is maintained.
[0076] As shown in FIG. 3, the suction device 49 includes the pipe 73. The pipe 73 has the suction opening 71 at one end in the longitudinal direction and is connected to the suction source 75 at the other end in the longitudinal direction. The suction opening 71 is directed to the yarn accumulation roller 41. A first valve (switching valve) 77 is provided at the intermediate part in the longitudinal direction of the pipe 73. The opening and closing of the first valve 77 are controlled by the unit controller 25. By controlling the first valve 77 to open, the suction air flow in the pipe 73 of the suction device 49 can be generated. By controlling the first valve 77 to close, the suction air flow in the pipe 73 can

be stopped. When the suction air flow is generated, a suction force acts on the outer circumferential surface of the yarn accumulation roller 41, and the spun yarn 7 which is wound around the outer circumferential surface (the spun yarn 7 remaining on the yarn accumulation roller 41) is sucked from the suction opening 71. As the spun yarn 7 is sucked into the inside of the pipe 73 from the suction opening 71, the spun yarn 7 can be restrained to a certain position with respect to the yarn accumulation roller 41. The suction source 75 is provided, for example, at the end of the spinning machine and is shared by a plurality of the spinning units 1.
[0077] The suction opening 71 is arranged to face a yarn introduction part 79 of the yarn accumulation device 17. The yarn introduction part 79 is an area of the outer circumferential surface of the yarn accumulation roller 41 at which the spun yarn 7 is positioned immediately before the spun yarn 7 is substantially started to be wound. [0078] The yarn introduction part 79 will now be described in detail. The yarn accumulation roller 41 has an accumulation part 41a formed in a cylindrical shape, on which the spun yarn 7 is wound spirally. In FIG. 3, the accumulation part 41a is illustrated as a cylindrical shape having a constant outer diameter, but it may be configured to have a tapered shape in which the outer diameter decreases in a stepwise or linear manner towards the downstream. As the package 9 rotates in the forward rotation direction and winds the spun yarn 7, the spun yarn 7 on the accumulation part 41a of the yarn accumulation roller 41 travels from upstream to downstream along a spiral path. The axis of the yarn accumulation roller 41 coincides with the spiral axis on which the spun yarn 7 is wound. At the end of the axis of the yarn accumulation roller 41 which corresponds to the upstream side of the spiral, the yarn accumulation roller 41 has a tapered part 41b. This tapered part 41b corresponds to the yarn introduction part 79. [0079] The yarn introduction part 79 is disposed at the upstream end area of the yarn

accumulation roller 41. Accordingly, the spun yarn 7 caught in the suction opening 71 of
the suction device 49 is restrained to be located in the vicinity of the upstream end area of
the yarn accumulation roller 41.
[0080] Hereinafter, the upstream side in the axial direction of the yarn accumulation
roller 41 means the upstream side of the spiral in the relevant axial direction, and the
downstream side in the axial direction means the downstream side of the spiral in the axial
direction.
[0081] The tapered part 41b is formed in a substantially conical shape having a larger
diameter than the accumulation part 41a. The diameter of the tapered part 41b decreases
as it approaches the accumulation part 41a and becomes equal to the diameter of the
accumulation part 41a at the point where it connects with the accumulation part 41a.
[0082] The yarn introduction part 79 is located upstream in the axial direction (lower
part in FIG. 3) of the yarn accumulation roller 41 compared to the most upstream part 80
where the spun yarn 7 is wound while being aligned in the accumulation part 41a. The
spun yarn 7 from the upstream side in the yarn travel direction is tensioned by the rotation
of the yarn accumulation roller 41, and is guided to the most upstream part 80 while making
contact with and being guided by the yarn introduction part 79 (tapered part 41b) as
necessary.
[0083] By rotating the yarn accumulation roller 41 while guiding the spun yarn 7 to a
certain position, the spun yarn 7 wound ahead of the spun yarn 7 in the accumulation part
41a is pushed by the spun yarn 7 wound after it and moves downstream in the axial direction
little by little. As a result, the spun yarn 7 can be accumulated in the accumulation part
41a in an orderly arrangement.
[0084] Referring to the timing chart in FIG. 4, the rotation control of the yarn
accumulation roller 41 and the package 9 in the case where the spun yarn 7 is disconnected

upstream of the yarn accumulation roller 41 will be described specifically. Timing tO is timing at which the spun yarn 7 is disconnected. In the case where the spun yarn 7 is disconnected, the unit controller 25 stops the rotation of the package 9 in the forward rotation direction and the rotation of the yarn accumulation roller 41 in the forward rotation direction at timing tl which is timing when a predetermined time has elapsed from the timing tO. Specifically, the unit controller 25 causes the drive of the winding drum drive motor and the drive of the yarn accumulation motor 43 to be stopped. The yarn end 7t of the spun yarn 7 on the package 9 side is wound onto the yarn accumulation roller 41 by the rotation of the yarn accumulation roller 41 in the forward rotation direction before it is stopped at the timing tl. At the timing tl, the yarn end 7t of the spun yarn 7 on the package 9 side is located near the most upstream part 80.
[0085] Thereafter, at timing t2, the unit controller 25 starts rotation of the yarn accumulation roller 41 in the backward rotation direction while keeping the rotation of the package 9 stopped. The unit controller 25 controls the first valve 77 to be opened at the timing t2 or a little earlier. As a result, a suction flow is generated in the suction device 49. The rotation of the yarn accumulation roller 41 in the backward rotation direction is continued until timing t3.
[0086] The rotation of the yarn accumulation roller 41 in the backward rotation direction causes the yarn end 7t of the spun yarn 7 on the package 9 side to be sucked into the suction device 49. As a result, the spun yarn 7 is unwound from the yarn accumulation roller 41 to the upstream side. As described above, the suction opening 71 of the suction device 49 is located so as to face the yarn introduction part 79. Therefore, in the process of rotating the yarn accumulation roller 41 in the backward rotation direction, the yarn end 7t located near the most upstream part 80 is easily sucked into the suction opening 71. In FIG. 3, the yarn end 7t in the state of being sucked into the suction device 49 is shown by the reference

numeral 7c.
[0087] The unit controller 25 stops the rotation of the yarn accumulation roller 41 in the backward rotation direction at the timing t3. The timing t3 is timing at which the yarn accumulation roller 41 has been rotated by a predetermined amount of rotation in the backward rotation direction.
[0088] The yarn accumulation roller 41 starts rotation in the forward rotation direction at the same timing t3, which is the same timing as the stop of rotation in the backward rotation direction. The rotation of the yarn accumulation roller 41 in the forward rotation direction is continued until timing t4. The rotation in the forward rotation direction may be started after a predetermined time elapses after the stop of the rotation in the backward rotation direction.
[0089] By the rotation of the yarn accumulation roller 41 in the forward rotation direction from the timing t3 to the timing t4, a part of the spun yarn 7 that had once been sucked into the suction device 49 is pulled out and wound onto the yarn accumulation roller 41. The suction opening 71 of the suction device 49 faces the yarn introduction part 79. Therefore, as the yarn accumulation roller 41 rotates in the forward rotation direction, the spun yarn 7 pulled out from the suction device 49 is naturally led from the yarn introduction part 79 to the most upstream part 80. Therefore, the spun yarn 7 can be aligned well in the accumulation part 41a.
[0090] From the timing t3 to the timing t4, the yarn accumulation roller 41 rotates in the forward rotation direction only a little. Specifically, the amount of rotation in the forward rotation direction of the yarn accumulation roller 41 is less than the amount of rotation in the backward rotation direction after the spun yarn 7 is disconnected. Therefore, at this point, the yarn end 7c of the spun yarn 7 on the package 9 side is not completely pulled out from the suction device 49. In other words, at the timing t4, the yarn end 7c remains inside

the suction device 49. That is, at this point in time, the yarn end 7c has not exited the suction opening 71.
[0091] A part of the spun yarn 7 is pulled out of the suction device 49 as the yarn accumulation roller 41 rotates in the forward rotation direction, but the suction device 49 acts a suction air flow in a direction that resists this pull. Accordingly, the suction device 49 also functions as a resistance action part that acts a resistance force that resists the spun yarn 7 from traveling in the direction of being wound onto the yarn accumulation roller 41. [0092] After the yarn accumulation roller 41 stops rotating in the forward rotation direction at the timing t4, the package 9 starts rotating in the forward rotation direction at timing t5. As a result, the spun yarn 7 is pulled toward the package 9, and the spun yarn 7 is unwound from the yarn accumulation roller 41 to the downstream side. At this time, since the yarn end 7c on the upstream side is being sucked into the suction device 49, the yarn end 7c is prevented from being entangled with the spun yarn 7 to be unwound. Therefore, the unwinding of the spun yarn 7 from the yarn accumulation roller 41 can be performed smoothly.
[0093] In the process in which the package 9 rotates in the forward rotation direction, the yarn end 7c starts to be pulled out from the suction device 49 almost at the same time as the spun yarn 7 is completely unwound from the yarn accumulation roller 41. Eventually, the yarn end 7c of the spun yarn 7 on the package 9 side is released from the suction device 49 and moves to the downstream side of the yarn accumulation device 17. Thereafter, the unit controller 25 controls the first valve 77 to be closed. This causes the suction flow of the suction device 49 to stop.
[0094] The significance of the control of rotating the yarn accumulation roller 41 in the backward rotation direction and forward rotation direction as shown in the timing t2 to the timing t4 will be explained below.

[0095] The spun yarn 7 is generated by twisting by the spinning device 13. Accordingly, when the spun yarn 7 is disconnected, the part near the yarn end 7t tends to deform in a certain direction under the influence of the torque of the twisting.
[0096] At the timing tl, the yarn end 7t is in a free state near the most upstream part 80 described above, as shown by the reference numeral 7a in FIG. 3. The yam end 7a in the free state is likely to contact the spun yarn 7 remaining wound around the accumulation part 41a, as shown by the reference numeral 7b, under the influence of the torque described above.
[0097] If the yarn end 7t, which is in the state indicated by the reference numeral 7b, becomes entangled with the spun yam 7 wound around the yam accumulation roller 41, it may cause tension fluctuations and/or yam breakage. Additionally, sloughing, in which the spun yam 7 on the yam accumulation roller 41 becomes entangled and clumps together and is released at once, may occur, and a mistake in unwinding the spun yarn 7 from the yarn accumulation roller 41 may occur.
[0098] One way to prevent the yarn end 7a from becoming entangled with the spun yarn 7 wound around the yarn accumulation roller 41 is to swing the yarn end 7a around by centrifugal force. For this purpose, in the process of pulling out and unwinding the spun yarn 7 from the yarn accumulation roller 41 towards the downstream, the yarn accumulation roller 41 may be rotated in the forward rotation direction at a certain speed. However, if the yarn accumulation roller 41 is rotated when the spun yarn 7 is unwound from the yarn accumulation roller 41 towards the downstream, an unintended change in the strength of the twists of the spun yarn 7 occurs between the yam accumulation roller 41 and the winding device 21.
[0099] In this regard, in the present embodiment, the yarn accumulation roller 41 is first rotated in the backward rotation direction to cause the free yam end 7a to be caught by the

suction device 49. As a result, the yarn end 7a is separated from the yarn accumulation roller 41 as shown by the reference numeral 7c. Thereafter, the yarn accumulation roller 41 is rotated slightly in the forward rotation direction while the suction device 49 continues sucking the spun yarn 7. As a result, the loosening of the spun yarn 7 between the suction device 49 and the yarn accumulation roller 41 is eliminated, and the spun yarn 7 is led from the suction opening 71 to the most upstream part 80 via the yarn introduction part 79. The rotation of the yarn accumulation roller 41 in the forward rotation direction performs a winding and tightening action of the spun yarn 7 on the outer circumferential surface of the yarn accumulation roller 41.
[0100] As a result of the above, the spun yarn 7 wound around the yarn accumulation roller 41 is regularly aligned in the accumulation part 41a. Accordingly, by rotating the package 9 in the forward rotation direction with the rotation of the yarn accumulation roller 41 stopped, the spun yarn 7 can be unwound from the yarn accumulation roller 41 one-wind by one-wind in a clean spiral shape and sent downstream. After (or almost at the same time as) the last wind of the spun yarn 7 is unwound from the yarn accumulation roller 41, the yarn end 7c exits the suction opening 71 of the suction device 49. Therefore, an entanglement of the yarn end 7t can be reliably prevented.
[0101] In the present embodiment, the yarn end 7t of the spun yarn 7 is restrained by acting the suction flow on the spun yarn 7 by the suction device 49. Since the air flow is used for the restraint, the vicinity of the yarn end 7t whose behavior is unstable can be flexibly restrained. In addition, the yarn end 7t of the spun yarn 7 can be easily controlled by the air flow.
[0102] The configuration in which the yarn end 7t of the spun yarn 7 is restrained using the air flow as in the present embodiment has an advantage that dirt such as fiber wastes is less likely to adhere to the yarn end 7t than the configuration in which some member (e.g.,

the plate-like guide described below) makes contact with the spun yarn 7 to restrain the spun yarn 7.
[0103] In the present embodiment, the first valve 77 is controlled by the unit controller 25 to be opened only when the spun yarn 7 is disconnected upstream of the yarn accumulation device 17. However, the first valve 77 may be opened at timing other than that described above. The first valve 77 may be omitted and the suction device 49 may be configured to generate a suction flow at all times. The suction device 49 can be used not only for restraining the yam end 7t when the spun yam 7 is disconnected upstream of the yarn accumulation device 17, but also for other objects.
[0104] In addition to the suction device 49, a plate-like guide for guiding the spun yarn 7 may be arranged upstream of the yarn accumulation roller 41 and downstream of the yam monitoring device 15. This plate-like guide can be made, for example, of a plate-shaped member. The plate-like guide guides the spun yam 7 by making contact with the spun yarn 7. As a result, the spun yarn 7 is guided to the yarn introduction part 79 of the yarn accumulation roller 41.
[0105] If the spun yam 7 is disconnected, for example at the spinning device 13, the behavior of the yarn end 7t of the spun yam 7 on the package 9 side is unstable. The plate¬like part of the plate-like guide prevents this yarn end 7t from moving irregularly to the yarn accumulation roller 41 side. This restriction prevents the yam end 7t of the spun yarn 7 from being entangled with the flyer 45, for example. As shown in FIG. 4, even after the spun yam 7 is disconnected, the yam accumulation roller 41 continues to rotate in the forward rotation direction. At this time, the plate-like guide urges the yam end 7t in the spun yam 7 on the package 9 side to pass through the plate-like guide at last and be wound onto the yarn accumulation roller 41. [0106] The plate-like guide makes contact with the spun yarn 7 and guides the spun yarn

7. Accordingly, when the spun yarn 7 is disconnected upstream of the yarn accumulation device 17 and the yarn accumulation roller 41 rotates in the forward rotation direction to wind the spun yarn 7 as described above, the plate-like guide applies a resistance force that resists the spun yarn 7 from traveling. As a result, tension is applied to the spun yarn 7 between the yarn accumulation roller 41 and the plate-like guide, so that the spun yarn 7 is stably guided to the yarn introduction part 79. Accordingly, the yarn end 7t of the spun yarn 7 is wound onto the yarn accumulation roller 41 in an orderly manner. [0107] The plate-like guide can also be arranged near the periphery of the yarn accumulation roller 41.
[0108] Next, control over the operation of the yarn release lever 51 shown in FIG. 1 will be described.
[0109] In the present embodiment, when the unwinding of the spun yarn 7 from the yarn accumulation roller 41 is completed, the yarn release lever 51 performs a yarn release operation. This yarn release operation may be referred to as the first yarn release operation. Timing at which the first yarn release operation is performed is later than timing at which the yarn end 7t of the spun yarn 7 leaves the yarn accumulation roller 41. The timing at which the first yarn release operation is performed may be referred to as first timing. [0110] The first yarn release operation will be described specifically. When the unit controller 25 determines that the unwinding of the spun yarn 7 from the yarn accumulation roller 41 has been completed, the unit controller 25 controls the winding device 21 so that the rotation of the package 9 stops. At approximately the same timing as the stopping of the rotation of the package 9, the unit controller 25 controls the yarn accumulation device 17 so as to move the yarn release lever 51 from the standby position to the yarn release position. [0111] Immediately after the spun yarn 7 wound around the yarn accumulation roller 41

has been completely unwound, the yarn end 7t of the spun yarn 7 on the package 9 side travels towards the downstream through the vicinity of the flyer 45, away from the yarn accumulation roller 41. In this process, the free yarn end 7t or a neighboring part thereof may contact the flyer 45 and become entangled. In the present embodiment, even in this case, the yarn end 7t or the neighboring part thereof can be released from the flyer 45 by the first yarn release operation which is described above. The moving timing of the yarn release lever 51 is not particularly limited, and can be at any time before the yarn joining is performed by the yarn joining device 19.
[0112] The first yarn release operation need not necessarily be performed. For example, a sensor to detect that the spun yarn 7 is not entangled with the flyer 45 may be provided, and the first yarn release operation may be performed only when the sensor detects entanglement of the spun yarn 7. Alternatively, the first yarn release operation may be omitted. In this embodiment, the first yarn release operation is performed at the timing when it is assumed that the spun yarn 7 is completely unwound from the yarn accumulation roller 41, and it is unknown whether the spun yarn 7 is actually unwound from the yarn accumulation roller 41.
[0113] The movement stroke (first movement amount) when the yarn release lever 51 performs the first yarn release operation is different from the movement stroke (second movement amount) when the yarn release lever 51 performs a second yarn release operation described below in other case. In other words, the yarn release position relative to the flyer 45 is different from that of the other case.
[0114] The other case is, for example, a case in which the spun yarn 7 from the yarn supply device 23 is led to the yarn joining device 19 by the guide device 57 in a series of yarn joining operations after the disconnection of the spun yarn 7. At this time, the spun yarn 7 guided by the guide device 57 is engaged with the flyer 45 which is rotating, and

winding of the spun yarn 7 onto the yarn accumulation roller 41 starts. After a predetermined amount (length) of the spun yarn 7 has been wound onto the yarn accumulation roller 41, the unit controller 25 moves the yarn release lever 51 from the standby position to the yarn release position. This yarn release operation may be referred to hereinafter as second yarn release operation. By this operation, the spun yarn 7 can be released from the flyer 45, and the spun yarn 7 wound onto the yarn accumulation roller 41 at the start of spinning can be suctioned and removed by the guide device 57. Thereafter, by the yarn release lever 51 returning to the standby position again, the spun yarn 7 is engaged with the flyer 45 and wound onto the yarn accumulation roller 41. Thereafter, this spun yarn 7 and the spun yarn 7 on the package 9 side which has already been prepared by the catching device 83, are joined by the yarn joining device 19. Timing at which the second yarn release operation is performed may be referred to hereinafter as second timing. The second timing is different from the first timing described above. [0115] When the flyer 45 is in contact with the vicinity of the free yarn end 7t, entanglement between the flyer 45 and the spun yarn 7 is more likely to occur than when the flyer 45 is in contact with the intermediate part of the spun yarn 7. Accordingly, in the present embodiment, the first movement amount is set to be more than the second movement amount. In other words, the yarn release position in the case of the first yarn release operation is farther away from the flyer 45 than the yarn release position in the case of the second yarn release operation. As a result, even if the yarn end 7t is entangled with the flyer 45, the yarn end 7t can be reliably released from the flyer 45 by the yarn release lever 51.
[0116] Next, the treatment of the yarn end of the spun yarn 7 on the package 9 side will be described. The treatment is performed after the spun yarn 7 is disconnected between the yarn supply device 23 and the yarn accumulation device 17 and the spun yarn 7 is

unwound from the yarn accumulation roller 41.
[0117] As shown in FIG. 5, the spinning unit 1 includes the detection device 81 capable of detecting the yarn end 7t of the spun yarn 7 on the package 9 side. The detection device 81 is capable of detecting the yarn end 7t located between the yarn accumulation device 17 and the winding device 21 after being unwound from the yarn accumulation roller 41. In the present embodiment, the detection device 81 is a sensor disposed downstream of the yarn accumulation roller 41 in the yarn travel direction. The detection device 81 is disposed closer to the yarn accumulation device 17 than to the winding device 21 in the yarn travel direction.
[0118] The detection device (sensor) 81 is, in the present embodiment, an optical reflection type sensor. The configuration of the detection device 81 is arbitrary. For example, the detection device 81 may be a capacitance type proximity sensor or a transmission type sensor.
[0119] The detection device 81 is disposed downstream of the guide 55. In detail, the detection device 81 is arranged between the guide 55 and the yarn joining device 19 in the yarn travel direction. The detection device 81 is arranged in the vicinity of the guide 55. The guide 55 guides the path of the spun yarn 7 in the vicinity of the detection device 81. [0120] When the spun yarn 7 is wound around the yarn accumulation roller 41 and the spun yarn 7 is tightened between the guide 55 and the winding device 21, the spun yarn 7 is located along the path 111 of the spun yarn 7 (part of the yarn travel path) shown by a chain line in FIG. 5. The detection device 81 is arranged to face an appropriate position of the path 111 of the spun yarn 7, and detects whether the spun yarn 7 is present at such a position.
[0121] Thus, when the spun yarn 7 is in a continuous state between the yarn supply device 23 and the winding device 21, the spun yarn 7 is located along the path 111, and the

detection device 81 detects that the spun yarn 7 is present. After the spun yarn 7 is disconnected, if the yarn end 7t of the spun yarn 7 on the package 9 side is located downstream of the detection device 81, the detection device 81 does not detect the spun yarn 7.
[0122] Even when the yarn end 7t of the spun yarn 7 on the package 9 side is upstream of the detection device 81, if the spun yarn 7 is not wound onto the yarn accumulation roller 41, the detection device 81 does not detect the spun yarn 7. The reason for this is that the spun yarn 7, which cannot maintain tension, is off the path 111 and is sucked into the catching device 83 described below. Thus, the detection device 81 detecting whether or not there is the spun yarn 7 in the path 111 of the spun yarn 7 is almost the same as detecting whether or not there is the yarn end 7t between the yarn accumulation roller 41 and the winding device 21.
[0123] The detection device 81 should be arranged with respect to a position where the movement of the spun yarn 7 is stable. For example, the detection device 81 may be disposed at any of the positions opposite the yarn accumulation roller 41 and in the area downstream than a center part of the yarn accumulation roller 41 in the axial direction, or near the suction device 49 (at a position adjacent to the yarn accumulation roller 41 in the direction intersecting the axial direction of the yarn accumulation roller 41). The yarn end 7t of the spun yarn 7 on the package 9 side that is detected by the detection device 81 does not refer only to a part in the spun yarn 7 where the spun yarn 7 completely ends, but includes this part and an area in the vicinity thereof.
[0124] The spinning unit 1 is provided with the catching device 83 that catches the spun yarn 7 at downstream of the yarn accumulation roller 41. The catching device 83 is located between the yarn accumulation device 17 and the winding device 21 in the yarn travel direction. In the present embodiment, as shown in FIG. 1, the catching device 83 is

disposed at a position which is located between the yarn accumulation device 17 and the yarn joining device 19 in the yarn travel direction, and in the vicinity of the detection device 81. The catching device 83 is located closer to the yarn accumulation device 17 than to the winding device 21 in the yarn travel direction.
[0125] The catching device 83 sucks and catches the yarn end 7t of the spun yarn 7 on the package 9 side when the spun yarn 7 is disconnected at upstream of the yarn accumulation device 17 in the yarn travel direction. When the catching device 83 sucks and catches the yarn end 7t, it does not have to suck firstly the part of the spun yarn 7 that completely ends with respect to the yarn end 7t. In other words, the catching device 83 may first suck a part of the spun yarn 7 that is close to the yarn end 7t and continue to suck, resulting in suction of the yarn end 7t.
[0126] The catching device 83 is provided with a pipe 85. In this embodiment, the catching device 83 is further provided with an air sucker 87 which generates a suction air flow when compressed air is supplied thereto.
[0127] The pipe 85 has a cylindrical shape. The pipe 85 is connected to the suction source 75 as a negative pressure source. Accordingly, the catching device 83 is capable of generating a suction air flow inside the pipe 85. The air sucker 87 is provided at one end of a longitudinal direction of the pipe 85. The air sucker 87 has a catching opening 89 for sucking the yarn end 7t of the spun yarn 7 on the package 9 side. The catching opening 89 is arranged to open toward the yarn path (path 111 of the spun yarn 7 in FIG. 5) formed between the yarn accumulation device 17 and the winding device 21. The relative position of the catching opening 89 to the yarn path is not particularly limited, and can be any position located downstream of the yarn accumulation roller 41 and in the vicinity of the yarn path. In the present embodiment, the catching opening 89 is fixedly provided in the spinning unit 1.

[0128] Compressed air generated by a compressed air source 91 is supplied to the air sucker 87. The air sucker 87 ej ects the compressed air through an ej ection hole (not shown in the drawings). As a result, an additional suction air flow in addition to the suction air flow by the suction source 75 can be generated at the catching opening 89. A second valve 93 is provided in the intermediate part of the compressed air supply path connecting the air sucker 87 to the compressed air source 91. The second valve 93 is an electromagnetic valve for switching whether or not to supply the compressed air to the air sucker 87. The opening and closing of the second valve 93 are controlled by the unit controller 25. By controlling the second valve 93 to open, the suction air flow is generated in the air sucker 87 (the catching device 83), and by controlling the second valve 93 to close, the suction air flow in the air sucker 87 is stopped.
[0129] Thus, in the present embodiment, the catching device 83 includes the air sucker 87. As a result, in the catching device 83, a strong suction air flow is generated in the catching opening 89 by the air flow produced by the air being ejected, and the yarn end 7t of the spun yarn 7 on the package 9 side can be sucked and reliably held. The catching device 83 does not necessarily have to be provided with the air sucker 87, as long as it can catch the yarn end 7t of the spun yarn 7 on the package 9 side with a sufficiently strong suction force.
[0130] The timing at which the catching device 83 operates the air sucker 87 for catching the yarn end 7t of the spun yarn 7 on the package 9 side is not particularly limited. For example, the unit controller 25 may operate the air sucker 87 at timing when it is determined that the amount of the spun yarn 7 remaining on the yarn accumulation roller 41 is less than a predetermined amount. The determination of the amount of the spun yarn 7 remaining on the yarn accumulation roller 41 can be based on the detection result of the yarn detection sensor 47.

[0131] In this embodiment, when the spun yarn 7 on the package 9 side is wound onto the package 9, the rotation of the package 9 is controlled by the unit controller 25. Specifically, it is as follows. By the rotation of the package 9 in the forward rotation direction, the spun yarn 7 (the spun yarn 7 on the package 9 side) is unwound from the yarn accumulation roller 41 to the downstream side as described above. Immediately after timing when the yarn end 7t of the spun yarn 7 leaves the yarn accumulation roller 41 due to the unwinding of the spun yarn 7 from the yarn accumulation roller 41, the yarn end 7t of this spun yarn 7 is caught by the catching device 83. As a result, when the detection device 81 no longer detects the spun yarn 7, the unit controller 25 stops the rotation of the package 9 in the forward rotation direction. This control allows the rotation of the package 9 in the forward rotation direction to be stopped before the yarn end 7t is completely wound onto the package 9.
[0132] The package 9 is then temporarily rotated in the backward rotation direction. This causes a part of the spun yarn 7 to be unwound from the package 9 and sucked into the catching device 83. The spun yarn 7 sucked into the catching device 83 is discarded when the yarn joining device 19 performs the yarn joining process. How much the package 9 is rotated in the backward rotation direction is adjusted according to the length of the yarn defect contained in the spun yarn 7 detected by the yarn monitoring device 15. As a result, when the yarn defect included in the spun yarn 7 on the package 9 side is short, the length of the spun yarn 7 sucked and removed by the catching device 83 can be shortened by reducing the amount of the rotation of the package 9 in the backward rotation direction. This can reduce the amount of the spun yarn 7 to be discarded. [0133] When the package 9 is temporarily rotated in the backward rotation direction, assuming that the suction force of the catching device 83 is insufficient, the spun yarn 7 on the package 9 side may not be unwound and may stick to the surface of the package 9

without leaving the surface of the package 9. When the package 9 is rotated in the backward rotation direction in this state, reverse winding occurs in which the spun yarn 7 is wound in a direction opposite to the normal direction. The reverse winding causes the failure of the yarn joining process by the yarn joining device 19 and the quality of the package 9 to decrease. However, in the present embodiment, by operating the air sucker 87 in the catching device 83, the spun yarn 7 can be strongly sucked and pulled into the catching opening 89. As a result, the occurrence of the reverse winding can be prevented. [0134] In the present embodiment, a first ejection device 97 is provided downstream of the yarn accumulation roller 41. The first ejection device 97 is located at a position opposite to the catching device 83 (catching opening 89) so as to sandwich the path 111 of the spun yarn 7. In other words, the first ejection device 97 and the catching device 83 (the catching opening 89) are provided on a straight line. Accordingly, the first ejection device 97 is capable of ejecting air toward the catching device 83 (the catching opening 89). The air ejected from the first ejection device 97 flows in the direction of the arrow 99 in FIG. 5 toward the catching opening 89 of the catching device 83. As a result, a neighboring part of the yarn end 7t of the spun yarn 7 on the package 9 side is blown towards the catching opening 89, so that the yarn end 7t can be caught more reliably by the catching device 83. Timing at which the first ejection device 97 performs the ejecting is not particularly limited. This timing may be, for example, the timing at which the yarn detection sensor 47 no longer detects the spun yarn 7, that is, the timing at which the spun yarn 7 is about to disappear from the yarn accumulation roller 41, or the timing at which the catching device 83 operates the air sucker 87.
[0135] Compressed air generated by a compressed air source 101 is supplied to the first ej ection device 97. The first ej ection device 97 ej ects this compressed air from the ej ection hole toward a path 111 of the spun yarn 7 (the catching opening 89 of the catching device

83). A third valve 103 is provided at the intermediate part of the compressed air supply path connecting the first ejection device 97 and the compressed air source 101. The third valve 103 is an electromagnetic valve for switching whether or not to supply compressed air to the first ejection device 97. The opening and closing of the third valve 103 are controlled by the unit controller 25. By controlling the third valve 103 to open, the compressed air is ejected in the first ejection device 97, and by controlling the third valve 103 to close, the ejection of the compressed air is stopped. The spinning unit 1 may be configured so that compressed air is supplied from a single compressed air source instead of providing the compressed air source 101 and the compressed air source 91 separately. [0136] In the present embodiment, as shown in FIG. 1, a second ejection device 105 is provided downstream of the first ejection device 97. The second ejection device 105 is fixedly provided on the spinning unit 1 or on a working cart (not shown in the drawings). The second ejection device 105 ejects compressed air so as to guide the yarn end 7t of the spun yarn 7 on the package 9 side toward the catching device 83 when the spun yarn 7 is disconnected between the yarn accumulation device 17 and the winding device 21 in the yarn travel direction. The second ejection device 105 can be configured in the same manner as the first ejection device 97. As a result, when the spun yarn 7 is disconnected downstream of the yarn accumulation device 17 in the yarn travel direction due to a failure of yarn joining in the yarn joining device 19 or for other reasons, by ejecting compressed air from the second ejection device 105 while rotating the package 9 in the backward rotation direction, the yarn end 7t of the spun yarn 7 on the package 9 side can be caught by the catching device 83. As a result, the yarn end 7t of the spun yarn 7 is guided to a position where the yarn joining device 19 can join the yarn. Accordingly, the spun yarn 7 on the package 9 side can be treated with a simple configuration. Simultaneously or at about the same time as the start of the ejection of compressed air from the second ejection

device 105, the package 9 is rotated in the backward rotation direction by the winding device 21. The second ejection device 105 may be omitted.
[0137] As described above, the spinning unit 1 provided in the spinning machine of this embodiment has the yarn supply device 23, the winding device 21, and the yarn accumulation device 17. The yarn supply device 23 can supply the spun yam 7. The winding device 21 winds the spun yam 7 supplied from the yarn supply device 23 to form the package 9. The yarn accumulation device 17 is disposed in a yam path (yam travel path) formed between the yarn supply device 23 and the winding device 21. The yarn accumulation device 17 includes the yarn accumulation roller 41 and the suction device 49. The yarn accumulation roller 41 winds and accumulates the spun yarn 7 supplied from the yarn supply device 23. When the spun yarn 7 is disconnected upstream of the yarn accumulation device 17 in the yam travel direction, the suction device 49 restrains the yarn end 7t of the spun yam 7 on the package 9 side with respect to the upstream end area of the yarn accumulation roller 41 by acting air on the yarn end 7t of the spun yam 7 on the package 9 side. After the spun yarn 7 is disconnected, while the suction device 49 acts air on the spun yarn 7, the package 9 is rotated in the forward rotation direction, which is the direction to wind the spun yarn 7 by the winding device 21 (after timing t5 in FIG. 4), so as to unwind the spun yam 7 remaining on the yarn accumulation roller 41 from the yarn accumulation roller 41. At the timing after the yarn end 7t of the spun yarn 7 on the package 9 side leaves the yam accumulation roller 41 and before the yam end 7t is wound onto the package 9, the rotation of the package 9 in the forward rotation direction, which has been continuing since timing t5, stops.
[0138] As a result, after the spun yarn 7 is disconnected upstream of the yarn accumulation device 17 in the yam travel direction, the spun yam 7 on the package 9 side can be properly treated with a simple configuration. By using air, the yam end 7t of the

spun yarn 7 on the package 9 side can be reliably restrained.
[0139] The spinning machine of this embodiment includes the first valve 77 and the unit
controller 25. The first valve 77 switches between generating and stopping the air flow in
the suction device 49. The unit controller 25 controls the first valve 77.
[0140] This makes it possible to generate the air flow only when necessary in the suction
device 49. Therefore, energy saving is realized.
[0141] In the spinning machine of the present embodiment, when the spun yam 7 is
disconnected upstream of the yam accumulation device 17 in the yam travel direction, the
suction device 49 acts to restrain the yarn end 7t (7a) of the spun yam 7 on the package 9
side with respect to the upstream end area of the yarn accumulation roller 41. The suction
device 49 includes the suction opening 71 facing the yarn accumulation roller 41, and the
yarn end 7t (7a) of the spun yarn 7 remaining on the yarn accumulation roller 41 is sucked
by the suction opening 71.
[0142] By sucking the yam end 7t (7a) of the spun yarn 7 remaining on the yarn
accumulation roller 41, the behavior of the spun yarn 7 can be stabilized. As a result, the
yarn end 7t does not become entangled with the spun yarn 7 so that the spun yarn 7
remaining on the yarn accumulation roller 41 can be easily unwound.
[0143] In the spinning machine of the present embodiment, the yarn accumulation roller
41 of the yarn accumulation device 17 includes the yarn introduction part 79 disposed
upstream of the most upstream part 80 where the spun yam 7 is wound around the outer
circumferential surface of the yam accumulation roller 41. The spun yarn 7 supplied from
the yarn supply device 23 is led to the most upstream part 80 of the yam accumulation roller
41 via the yarn introduction part 79. The suction opening 71 of the suction device 49 is
arranged to face the yarn introduction part 79.
[0144] This ensures that the yarn end 7t (7a) of the spun yarn 7 remaining on the yarn

accumulation roller 41 is sucked by the suction opening 71 of the suction device 49. [0145] In the spinning machine of this embodiment, the yarn accumulation roller 41 accumulates the spun yarn 7 by being rotated in the forward rotation direction which is the direction in which the spun yarn 7 from upstream is wound. When the spun yarn 7 is disconnected upstream of the yarn accumulation device 17 in the yarn travel direction, the rotation of the package 9 and the yarn accumulation roller 41 in the forward rotation direction are stopped respectively. After each of the package 9 and the yarn accumulation roller 41 has stopped being rotated in the forward rotation direction, the yarn accumulation roller 41 is rotated in the backward rotation direction.
[0146] As a result, the yarn end 7t (7a) of the spun yarn 7 remaining on the yarn accumulation roller 41 is unwound towards the upstream by the rotation of the yarn accumulation roller 41 in the backward rotation direction. Therefore, the yarn end 7t can be more reliably sucked by the suction opening 71 of the suction device 49. [0147] In the spinning machine of this embodiment, the yarn accumulation roller 41 is rotated in the forward rotation direction after the yarn accumulation roller 41 has been rotated in the backward rotation direction.
[0148] As a result, the yarn accumulation roller 41 is rotated in the forward rotation direction while the spun yarn 7 is being sucked in the suction opening 71. Therefore, the yarn accumulation roller 41 generates a winding and tightening action on the spun yarn 7 that is continuous between the package 9 and the yarn accumulation roller 41. This causes the spun yarn 7 remaining on the yarn accumulation roller 41 to be lined up in an orderly manner. Therefore, the spun yarn 7 remaining on the yarn accumulation roller 41 can be unwound smoothly from the yarn accumulation roller 41.
[0149] In the spinning machine of this embodiment, compared to the amount of rotation when the yarn accumulation roller 41 is rotated in the backward rotation direction, the

amount of rotation when the yarn accumulation roller 41 is rotated in the forward rotation direction after the yarn accumulation roller 41 has been rotated in the backward rotation direction is smaller.
[0150] This prevents the yarn end 7t (7c), which has been sucked into the suction opening 71 of the suction device 49 when the yarn accumulation roller 41 has been rotated in the backward rotation direction, from exiting the suction opening 71 when the yarn accumulation roller 41 is rotated in the forward rotation direction. Accordingly, the action by the suction device 49 can be continued.
[0151] In the spinning machine of this embodiment, the yarn accumulation device 17 includes the flyer 45 and the yarn release lever 51. The flyer 45 rotates relative to the yarn accumulation roller 41. The spun yarn 7 unwound from the yarn accumulation roller 41 is engaged with the flyer 45. The yarn release lever 51 performs the yarn release operation to release the yarn travel path from the flyer 45 at the first timing. The first timing is later than the timing at which the yarn end 7t of the spun yarn 7 on the yarn accumulation roller 41 (the spun yarn 7 on the package 9 side) leaves the yarn accumulation roller 41. [0152] As a result, when the yarn end 7t of the spun yarn 7 on the yarn accumulation roller 41 leaves the yarn accumulation roller 41, even if the yarn end 7t is entangled with the flyer 45, this yarn end 7t can be released from the flyer 45 by the yarn release lever 51. [0153] In the spinning machine of the present embodiment, the yarn release lever 51 is configured to perform the yarn release operation at the second timing different from the first timing. The first movement amount of the yarn release lever 51 with respect to the yarn release operation performed at the first timing is different from the second movement amount of the yarn release lever 51 with respect to the yarn release operation performed at the second timing. [0154] As a result, when the yarn end 7t of the spun yarn 7 on the yarn accumulation

roller 41 leaves the yarn accumulation roller 41, even if the yarn end 7t is entangled with
the flyer 45, the yarn end 7t can be reliably released from the flyer 45 by the yarn release
operation different from the others.
[0155] In the spinning machine of this embodiment, the yarn supply device 23, the
winding device 21, and the yarn accumulation device 17 are provided in each of the
plurality of the spinning units 1.
[0156] This makes it easier to use the yarn supply device 23, the winding device 21, and
the yarn accumulation device 17.
[0157] In the spinning machine of this embodiment, each of the plurality of the spinning
units 1 includes the drive unit for the winding device 21. When the winding device 21
includes the winding drum 63 having the traverse groove, the drive unit is the winding drum
drive motor. When the winding device 21 includes a winding drum without a traverse
groove and a traverse guide that is provided independently of the winding drum and
reciprocates, each of a winding drum drive motor and a traverse guide drive motor
corresponds to the drive unit.
[0158] This allows control to independently drive and stop the winding device 21 for
each spinning unit 1.
[0159] In the spinning machine of this embodiment, each of the plurality of the spinning
units 1 includes a drive unit for the yarn release lever 51.
[0160] As a result, unlike the conventional configuration, the yarn release lever 51 can
be controlled to operate independently for each spinning unit 1.
[0161] The spinning method of this embodiment is performed on the spinning unit 1
including the yarn supply device 23, the winding device 21, and the yarn accumulation
device 17. The yarn supply device 23 can supply the spun yarn 7. The winding device
21 winds the spun yarn 7 supplied from the yarn supply device 23 to form the package 9.

The yarn accumulation device 17 is disposed in the yam path (yarn travel path) formed between the yarn supply device 23 and the winding device 21. The above-described spinning machine performs spinning while rotating the package 9 in the forward rotation direction which is the direction in which the spun yarn 7 is wound. The yarn accumulation device 17 includes the yarn accumulation roller 41 and the suction device 49. The yam accumulation roller 41 is capable of winding and accumulating the spun yarn 7 supplied from the yam supply device 23. The suction device 49 restrains the yarn end 7t of the spun yarn 7 on the package 9 side with respect to the upstream end area of the yarn accumulation roller 41 by acting air on the yarn end 7t of the spun yam 7 on the package 9 side when the spun yarn 7 is disconnected upstream of the yarn accumulation device 17 in the yarn travel direction. After the spun yam 7 is disconnected, while the suction device 49 acts air on the spun yarn 7, the package 9 is rotated in the forward rotation direction by the winding device 21 (after timing t5 in FIG. 4) so as to unwind the spun yam 7 remaining on the yarn accumulation roller 41 from the yam accumulation roller 41. The rotation of the package 9 in the forward rotation direction that has been continuing since the timing t5 is stopped at the timing after the yarn end 7t of the spun yam 7 on the package 9 side leaves the yam accumulation roller 41 and before the yarn end 7t is wound onto the package 9. [0162] As a result, the spun yarn 7 on the package 9 side can be properly treated after the spun yarn 7 is disconnected upstream of the yam accumulation device 17 in the yam travel direction.
[0163] While some preferred embodiments of the present invention have been described above, the foregoing configurations may be modified, for example, as follows. The above embodiments and the following modifications can be combined as appropriate. [0164] Instead of the suction device 49, an ejection device (yarn acting part) may be provided to eject air in vicinity of the yam accumulation roller 41. This ejection device

may be configured to eject air on the circumference of the yarn accumulation roller 41. This ejection device may be configured, for example, to eject air in a tangential direction to the yarn accumulation roller 41 at the most upstream part 80 described above. The direction of the air ejection may coincide with or differ from the direction of the suction air flow at the suction opening 71 shown in FIG. 3. The part of the spun yam 7 on the package 9 side, which is upstream of the yarn accumulation roller 41, is blown away along with the ejection flow. As a result, the yarn end 7a in a free state can be prevented from contacting against the spun yarn 7 already wound around the accumulation part 41a. In this way, the ejection device can substantially restrain the spun yarn 7. The ejection of air from the ejection device can also provide a resistance force to resist the spun yam 7 from traveling in the direction of being wound onto the yam accumulation roller 41. As with the suction device 49, a first valve 77 can be provided between the compressed air source and the opening of the ejection device, and the opening and closing of the first valve 77 can be controlled by the unit controller 25.
[0165] In place of the suction device 49, a suitable clamping device (yam acting part) configured to be able to clamp the yarn end 7t of the spun yarn 7 on the package 9 side may be provided. The spun yam 7 may be clamped between arms arranged in pairs or between rollers arranged in pairs. The clamping device can restrain the spun yam 7 from moving by clamping the spun yarn 7. For example, a damper can be provided on the shaft of the roller to provide a resistance force to resist the spun yam 7 from traveling in the direction of being wound onto the yarn accumulation roller 41.
[0166] When a roller pair is provided as a yam acting part, the roller pair may perform the pull-out operation to pull out the spun yarn 7 from the spinning device 13. In this case, the yam accumulation roller 41 accumulates the spun yarn 7 pulled out by the roller pair. [0167] Instead of the suction device 49, a brush or comb teeth or the like (yarn acting

part) may be provided to engage the spun yarn 7. By engaging the spun yarn 7 onto the brush or the like, the spun yarn 7 can be restrained so that it does not move. [0168] When the spinning unit 1 includes the ejection device, roller pair, brush, or comb teeth described above as the yarn acting part, the rotation of the yam accumulation roller 41 in the backward rotation direction for sucking the spun yarn 7 into the suction opening 71 of the suction device 49 may be omitted. In this case, after the spun yam 7 is disconnected, the rotation of the yam accumulation roller 41 and/or the rotation of the package 9 need not be stopped once in connection with the operation of the yarn acting part. [0169] The detection device 81 may be a sensor as follows. That is, the sensor is provided with respect to the outer circumferential surface of the yam accumulation roller 41, at a downstream end in the yarn travel direction than the center part of the axial direction of the yarn accumulation roller 41 . The sensor is arranged so as to face the downstream end of the outer circumferential surface described above. The sensor is arranged at a position so as to face the roller surface downstream in the yam travel direction than the center part of the axial direction of the yam accumulation roller 41. In the case where the spinning unit 1 includes a restriction means for restricting the yarn path of the spun yarn 7 traveling from the yam accumulation roller 41 through the flyer 45, the yarn path may be restricted by the restriction means. The restriction means may be, for example, a member which is provided near the flyer 45 of the yam accumulation device 17 and which may stop the rotation of the flyer 45. By the restriction means restricting the yarn path, the yam end 7t can be stably detected by the sensor.
[0170] The detection device 81 may be a line sensor. The line sensor is disposed along the axial direction of the yam accumulation roller 41 at a position adjacent to the yarn accumulation roller 41. The line sensor faces the outer circumferential surface of the accumulation part 41a. The line sensor includes a plurality of detection elements arranged

in a direction parallel to the axial direction of the yarn accumulation roller 41. The line
sensor is provided to detect a position included in an area downstream in the yarn travel
direction than the center part of the axial direction of the yam accumulation roller 41.
When all the detection elements no longer detect the spun yam 7, it can be determined that
the yam end 7t has passed through the outer circumferential surface of the yam
accumulation roller 41.
[0171] The detection device 81 may be a sensor provided in the vicinity of the suction
opening 71 of the suction device 49. When the spun yarn 7 is completely unwound from
the yarn accumulation roller 41, the yarn end 7c is pulled out of the suction opening 71.
Therefore, by arranging the sensor in the vicinity of the suction opening 71, the yarn end 7t
(7c) can be stably detected.
[0172] In the above-described embodiment, when the yarn monitoring device 15 detects
the yam defect, the spun yarn 7 is cut by stopping spinning in the spinning device 13.
Alternatively, the spun yarn 7 may be cut by a cutter provided upstream of the yarn
accumulation device 17.
[0173] In a case where a plurality of the spinning units 1 are provided, instead of a
configuration in which the yarn joining device 19 is provided for each spinning unit 1, a
configuration in which a yarn joining cart is provided which is capable of traveling among
the plurality of the spinning units 1 and stopping at a working position for the spinning unit
1 to perform the yarn joining as needed may be adopted.
[0174] In the above embodiment, the spinning unit 1 includes a layout in which a yarn
path formed between the yarn supply device 23 and the winding device 21 is provided so
as to go from bottom to top. However, the present invention can also be applied to the
spinning unit 1 with a layout in which the yarn path goes from top to bottom.
[0175] In the above embodiment, the spinning machine is an air spinning machine (air

jet spinning machine), but it can also be an open-end spinning machine.
[0176] In the above embodiment, the yarn end 7t of the spun yarn 7 unwound from the
yarn accumulation roller 41 is caught by the catching device 83. However, the spinning
unit 1 may not include the catching device 83, and each device may be controlled so that
the yam end 7t stops at any position between the yam accumulation roller 41 and the
package 9.
[0177] When the catching device 83 is not provided, the first ejection device 97 and/or
the detection device 81 may be omitted. Even when the catching device 83 is provided,
the first ejection device 97 may be omitted.
[0178] In the above embodiment, after the yam end 7t of the spun yam 7 is sucked and
caught by the suction device 49, the yarn accumulation roller 41 is rotated in the forward
rotation direction. This rotation in the forward rotation direction may be omitted.
[0179] In the above embodiment, the spun yam 7 on the package 9 side is joined with
the spun yarn 7 supplied from the yarn supply device 23 by the yarn joining device 19.
However, the disconnected spun yarn 7 may be made continuous state again by a known
piecing method.
[0180] In view of the foregoing teachings, it is apparent that the present invention may
take many variation forms and modification forms. Accordingly, it is to be understood
that the invention may be practiced in a manner other than that described herein within the
scope of the appended claims.
DESCRIPTION OF THE REFERENCE NUMERALS
[0181] 7 spun yarn (yarn)
9 package
17 yarn accumulation device

21 winding device
23 yarn supply device
41 yarn accumulation roller
45 flyer (yam engaging member)
49 suction device (yam acting part)
51 yarn release lever (yarn release member)
71 suction opening
79 yarn introduction part

WE CLAIM
1. A spinning machine comprising:
a yarn supply device (23) capable of supplying yarn (7);
a winding device (21) for winding the yarn (7) supplied from the yarn supply device (23) to form a package (9); and
a yarn accumulation device (17) disposed in a yarn travel path formed between the yarn supply device (23) and the winding device (21), wherein
the yarn accumulation device (17) includes:
a yarn accumulation roller (41) for winding and accumulating the yarn (7) supplied from the yarn supply device (23); and
a yarn acting part (49) that restrains a yarn end of the yarn (7) on a package (9) side with respect to an upstream end area of the yarn accumulation roller (41) by acting air on the yarn end of the yarn (7) on the package (9) side when the yarn (7) is disconnected upstream of the yarn accumulation device (17) in a yarn travel direction,
after the yarn (7) is disconnected, while the yarn acting part (49) acts air on the yarn (7), the package (9) is rotated in a forward rotation direction, which is a direction to wind the yarn (7) by the winding device (21), so as to unwind the yarn (7) remaining on the yarn accumulation roller (41) from the yarn accumulation roller (41), and
rotation of the package (9) in the forward rotation direction is stopped at timing after the yarn end of the yarn (7) on the package (9) side leaves the yarn accumulation roller (41) and before the yarn end is wound onto the package (9).
2. The spinning machine as claimed in claim 1, comprising:
a switching valve (77) that switches between generating and stopping an air flow

by the yarn acting part (49); and
a control device (25) for controlling the switching valve (77).
3. The spinning machine as claimed in claim 1 or 2, wherein
the yarn acting part (49) is a suction device (49), and
the suction device (49) includes a suction opening (71) facing the yarn accumulation roller (41), and the yarn end of the yam (7) remaining on the yam accumulation roller (41) is sucked by the suction opening (71).
4. The spinning machine as claimed in claim 3, wherein
the yarn accumulation device (17) includes a yarn introduction part (79) disposed upstream of the most upstream part where the yarn (7) is wound around an outer circumferential surface of the yam accumulation roller (41),
the yarn (7) supplied from the yarn supply device (23) is led to the most upstream part of the yarn accumulation roller (41) via the yarn introduction part (79), and
the suction opening (71) is arranged to face the yam introduction part (79).
5. The spinning machine as claimed in claim 3 or 4, wherein
the yarn accumulation roller (41) accumulates the yam (7) by rotating in a forward rotation direction which is a direction for winding yam (7) from upstream,
when the yam (7) is disconnected upstream of the yarn accumulation device (17) in the yam travel direction, rotation of each of the package (9) and the yam accumulation roller (41) in the forward rotation direction is stopped, and
after each of the package (9) and the yarn accumulation roller (41) has stopped rotating in the forward rotation direction, the yarn accumulation roller (41) rotates in a

backward rotation direction.
6. The spinning machine as claimed in claim 5, wherein
the yam accumulation roller (41) rotates in the forward rotation direction after the yam accumulation roller (41) has rotated in the backward rotation direction.
7. The spinning machine as claimed in claim 6, wherein
compared to an amount of rotation when the yarn accumulation roller (41) rotates in the backward rotation direction, an amount of rotation when the yarn accumulation roller (41) rotates in the forward rotation direction after the yarn accumulation roller (41) has rotated in the backward rotation direction is smaller.
8. The spinning machine as claimed in claim 1, wherein
the yam acting part (49) is an ejection device that ejects air in vicinity of the yarn accumulation roller (41).
9. The spinning machine as claimed in any one of claims 1 to 8, wherein
the yarn accumulation device (17) includes:
a yarn engaging member (45) that rotates relative to the yam accumulation roller (41) and with which the yarn (7) unwound from the yarn accumulation roller (41) is engaged; and
a yarn release member (51) that performs a yarn release operation to release the yarn travel path from the yam engaging member (45) at first timing which is timing later than timing at which the yarn end of the yam (7) on the package (9) side leaves the yam accumulation roller (41).

10. The spinning machine as claimed in claim 9, wherein
the yarn release member (51) is configured to perform the yarn release operation at second timing different from the first timing, and
a first movement amount of the yarn release member (51) with respect to the yarn release operation performed at the first timing is different from a second movement amount of the yarn release member (51) with respect to the yarn release operation performed at the second timing.
11. The spinning machine as claimed in any one of claims 1 to 10, wherein
the yarn supply device (23), the winding device (21), and the yarn accumulation device (17) are provided in each of the plurality of spinning units (1).
12. The spinning machine as claimed in claim 11, wherein
each of the plurality of the spinning units (1) includes a drive unit for the winding device (21).
13. The spinning machine as claimed in claim 11 or 12, wherein
in each of the plurality of the spinning units (1), the yarn accumulation device (17) includes:
a yarn engaging member (45) that rotates relative to the yarn accumulation roller (41) and with which the yarn unwound from the yarn accumulation roller (41) is engaged; and
a yarn release member (51) that performs a yarn release operation to release the yarn travel path from the yarn engaging member (45) later than timing at which the yarn

end of the yarn (7) on the package (9) side leaves the yarn accumulation roller (41), and
each of the plurality of the spinning units (1) includes a drive unit for the yarn release member (51).
14. A spinning method performed on a spinning machine comprising:
a yarn supply device (23) capable of supplying yarn (7);
a winding device (21) for winding the yarn (7) supplied from the yarn supply device (23) to form a package (9); and
a yarn accumulation device (17) disposed in a yarn travel path formed between the yarn supply device (23) and the winding device (21), wherein
the yarn accumulation device (17) includes:
a yarn accumulation roller (41) for winding and accumulating the yarn (7) supplied from the yarn supply device (23); and
a yarn acting part (49) that restrains a yarn end of the yarn (7) on a package (9) side with respect to an upstream end area of the yarn accumulation roller (41) by acting air on the yarn end of the yarn (7) on the package (9) side when the yarn (7) is disconnected upstream of the yarn accumulation device (17) in a yarn travel direction,
after the yarn (7) is disconnected, while the yarn acting part (49) acts air on the yarn (7), the package (9) is rotated in a forward rotation direction, which is a direction to wind the yarn (7) by the winding device (21), so as to unwind the yarn (7) remaining on the yarn accumulation roller (41) from the yarn accumulation roller (41), and
rotation of the package (9) in the forward rotation direction is stopped at timing after the yarn end of the yarn (7) on the package (9) side leaves the yarn accumulation roller (41) and before the yarn end is wound onto the package (9).