JP3586753B2 - Peeing method and apparatus in spinning machine - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a method of piecing a cut yarn in a spinning device.
[0002]
[Prior art]
Conventionally, in a spinning device using an air spinning nozzle,Fiber bundleIs drafted by a draft device comprising three or more draft roller pairs, and then twisted by a swirling airflow generated by compressed air injection in an air spinning nozzle to produce a spun yarn.
[0003]
In such a spinning device, when the spun yarn breaks, or when a yarn defect such as a slab is detected in the spun yarn and the yarn is forcibly cut, the lower yarn pulled out from the winding side is used. And the upper yarn newly spun by the air spinning nozzle and sent to the downstream side are spliced by a mechano-notter or a splicer. In these methods, since yarns are spliced together, there is naturally a limit in improving the composition and appearance of the seam. Therefore, a method of piecing the yarn in the spinning process and the yarn end on the winding side by resuming spinning after passing the yarn end on the winding side back to the air spinning nozzle has been proposed. In the piecing method, the position of the yarn end on the take-up side at the time of piecing is unstable, so that the fiber may jump out of the seam portion, and furthermore, the seam length is not always constant, and the strength and appearance of the seam There is a problem that variation occurs in
[0004]
[Problems to be solved by the invention]
An object of the present invention is to provide a piecing method capable of stably performing piecing with good seam strength and appearance in view of the above-described points of the related art.
[0005]
[Means for Solving the Problems]
The spun yarn end is passed through the twisting means, pulled out to the reference roller upstream side of the draft device, and the yarn end is passed through the draft device.Fiber bundleThe draft device and the twisting means are operated while being guided to the center in the width direction on the locus. Means for passing the spun yarn end from downstream of the twisting means to upstream of the reference roller of the drafting device(Thread end guidance device)And catch the yarn end passed on the upstream side of the reference roller of the draft deviceConsists of suction nosulYarn end catching means,A yarn end detecting means provided at a predetermined position in the suction nozzle, a control device for restarting the movement of the spinning unit based on the yarn end detection of the yarn end detecting means,The yarn end captured by the yarn end capturing means passes through the draft device at a reference roller upstream side of the draft device.Fiber bundleAnd a yarn guide that guides the yarn at the center in the width direction on the trajectory. The yarn end catching means is a suction nozzle for sucking and capturing the yarn end, and the suction port of the suction nozzle is formed in a flat shape narrowed in the width direction so as to also serve as a yarn guide, and the yarn guide is provided in a draft device. Is fixedly provided.
[0006]
[Action]
At the time of the piecing operation, the yarn drawn out of the package is passed from the downstream side of the twisting means to the upstream side and drawn out upstream of the reference roller of the draft roller, and the end of the drawn out yarn is held by the suction nozzle of the yarn holding means. When the yarn end is detected by the yarn end detecting means when the yarn end is pulled out from the suction nozzle by the forward rotation of the package when the spinning is restarted, the operation of the spinning unit is restarted, and the drafting device and the twisting means are operated. By activating, piecing is performed in a state where the yarn end and the fiber bundle are overlapped by a certain length.
Draft deviceofActuationTime,Pulled out of the suction nozzleThe spun yarn ends have been draftedFiber bundleIs guided to the center in the width directionFiber bundleIn the center in the width direction ofFiber bundleDraft with. And left the draft deviceFiber bundleAnd the yarn end is twisted by twisting means. At this time,Fiber bundleAt the center in the width direction of theFiber bundleIs wrapped and twisted, resulting in a new thread endFiber bundleA seam is formed that is hardly distinguished from other parts in appearance.
[0007]
【Example】
An embodiment will be described with reference to the drawings.
[0008]
1 and 2 are a front view and a side sectional view showing a spinning machine 1 for carrying out the method of the present invention. In the figure, a spinning machine 1 includes a draft device 2, a pneumatic spinning nozzle 3, which is a twisting means, and a false twist device 4, a delivery roller 5, a yarn clearer 6, and a winding device 7, which are arranged in series from an upstream side to a downstream side. A plurality of spinning units 1u are provided side by side, and a self-propelled work vehicle 8 that reciprocates in the machine longitudinal direction of the spinning machine 1 along each of the spinning units 1u is provided.
[0009]
The draft device 2 includes a four-line draft roller pair consisting of a back roller pair 21, a third roller pair 22, a middle roller pair 23 with an apron belt 23e mounted thereon, and a front roller pair 24.Fiber bundleThe trumpet guide for introducing S into the back roller pair 21, 26Fiber bundleThis is a capacitor that regulates the width of S. Among the draft roller pairs, the front roller pair 24 has its bottom roller provided on a line shaft common to each unit and is driven simultaneously by all units. However, the other rollers can be stopped for each unit. ing.
[0010]
Each top roller of the draft device 2 is rotatably supported by a draft cradle 29, and is pressed against each bottom roller by a biasing member (not shown) provided on the draft cradle 29. The top roller 24t of the roller pair 24 can be lifted and separated from the bottom roller 24b independently of the other rollers by an operation from the work vehicle 8 side during piecing.
[0011]
As shown in FIG. 3, the pneumatic spinning nozzle 3 is disposed downstream of the front roller pair 24, opens a compressed air injection hole 33 in a tangential direction on the inner surface of the nozzle, and injects compressed air from the compressed air injection hole 33. Accordingly, a swirling airflow in a direction opposite to a twisting direction of a twisting device 4 described later can be generated in the air spinning nozzle 3. Since the compressed air injection holes 33 are provided so as to be inclined toward the yarn running direction, suction airflow is likely to be generated near the inlet 31 of the air spinning nozzle 3.
[0012]
Numeral 34 denotes an air supply pipe for sending compressed air to the air spinning nozzle 3. The air supply pipe 34 is connected to a pressure source (not shown), and is operated at a predetermined position during the piecing operation by the work cart 8 to stop air supply. The supply of the compressed air to the spinning nozzle 3 is stopped.
[0013]
The pneumatic spinning nozzle 3 is fixed to the tip of the swing arm 35 as shown in FIG. 1, and moves upward from the spinning position by an operation from the work cart 8 during piecing.
[0014]
The false twisting device 4 includes a pair of rollers 41 and 42 that are supported in contact with each other in the axial direction as shown in FIGS. 3 and 8. Each of the rollers 41 and 42 is a hollow roller formed by externally fitting a thin roller made of a flexible elastic material such as rubber on a roller core body, and has a central portion having an arc-shaped cross section with respect to both peripheral surface ends. It has an outer shape of a bulging barrel. The rollers 41 and 42 are rotatably supported by brackets 43 and 44 via bearings, and are provided with pulleys 45 and 46 provided at ends of the respective rotating shafts and pulleys 49 fixed to the rotating shaft of the motor 50. Between them, belts 47 and 48 are wound around, respectively, and are synchronously rotated at a constant peripheral speed by the motor 50.
[0015]
During normal spinning, the delivery roller 5 is biased by a spring (not shown) to be a nip roller.51Can be sent out by pressing, but at the time of piecing,OfBy operation, the nip roller 51 is separated from the delivery roller 5 against the urging force of the spring, and the feeding of the spun yarn Y is stopped.
[0016]
The yarn clearer 6 is a detecting device for detecting yarn defects such as slabs, fine yarns, and thick yarns generated in the spun yarn Y, and yarn breakage. When these are detected, a control signal is output to stop the spinning and The work cart 8 is stopped by the spinning unit 1u to perform piecing.
[0017]
The winding device 7 is rotatably supported by the cradle arm 73 while traversing the yarn Y by the traverse guide 71, and winds the package Y which is pressed against the friction roller 72 and rotates.
[0018]
As shown in FIGS. 1 and 2, the work cart 8 reciprocates between a number of spinning units 1 u of the spinning machine 1 along a plurality of rails 81 and 82 provided over the entire length of the spinning machine 1. The work carriage 8 is movable, and a suction mouth 9 for sucking and drawing out the spun yarn end wound on the winding package P at the time of piecing, and a yarn end drawn out by the suction mouth 9 is used as a yarn end. A yarn guiding device 10 for guiding to a guiding device 11, a yarn end guiding device 11 for guiding the yarn end to the pneumatic spinning nozzle 3, and a yarn reversing nozzle 12, a cutter 13, a clamp 14, and a clamp 14 attached thereto; The yarn which has been inserted into the pneumatic spinning nozzle 3 is sucked and captured by the slack tube 15 in which the yarn is previously loosened, and the yarn is drawn out to the upstream side of the front roller 24 (reference roller) of the draft device 2. The suction nozzle 16 is provided as a catching means.
[0019]
Further, the work carriage 8 is brought into contact with a cradle boss 74 integrated with the cradle arm 73 of the winding device 7, and a grip lever 83 for positioning the cradle arm 73 at an arbitrary swing angle, and for rotating the winding package P in the reverse direction. A reverse roller 84, a revolving arm 85 for pressing the reverse roller 84 against the package P, a package pressing plate 86 for pressing the package P and separating it from the friction roller 72, and removing the yarn on the winding side from the traverse guide 71. A guide 87 is provided, and a plurality of cams 88 for controlling the operation and timing thereof are provided.
[0020]
As shown in FIG. 1, the yarn guiding device 10 includes a yarn locking arm 101 supported rotatably about a vertical axis and a yarn guide arm 102 supported rotatably about a horizontal axis. At the time of piecing, it reciprocates about 180 ° between each position shown by the solid line in FIG. 1 and each position shown by the two-dot chain line in FIG.
[0021]
The yarn end guiding device 11 is provided with a yarn reverse feed nozzle 12 shown in FIG. 5 at the tip of an arm 112 rotatably supported by a bracket 111 at the upper end of the frame of the work cart 8 as shown in FIG. A cutter 13 and a clamp 14 are provided on both sides of the yarn reverse feed nozzle 12. And the yarn end guiding device 11ofA segment gear 114 meshes with a gear 113 provided integrally with a rotating shaft of the arm 112, and the segment gear 114 is rotated by a cam 88 which controls each operation of piecing to thereby provide a yarn end guiding device. Numeral 11 is adapted to swing up and down, and at the descending end of the orbit, the yarn reverse feed nozzle 12 is positioned beside the yarn guide device 10 and at the ascending end of the swivel orbit shown in FIG. As shown, the yarn reverse feed nozzle 12 can be positioned above the yarn path between the air spinning nozzle 3 and the false twist device 4.
[0022]
As shown in FIG. 1, the suction nozzle 16 is rotatably supported at its base end by a bracket 161 at the upper end of the frame of the work vehicle 8 and is fixed to a pipe forming its rotation axis.WasA segment gear 163 meshes with the integral gear 162. By rotating the segment gear 163 with the cam 88 described above, the segment gear 163 swings in the vertical direction and, as shown in FIG. However, it is foldable with respect to the base end portion 16b. That is, the distal portion 16a is swingably connected to the proximal portion 16b by the hinge 165, forms a four-bar link with the portions 16a and 16b, and urges the distal portion 16a in a direction in which the distal portion 16a is extended. Each arm of the spring 166 is rotatably connected to the above 16a, 16b. Further, a pin 167 is provided at the distal end of the arm on the suction nozzle base end side portion 16b side of the spring 166, and the work carriage 8 comes into contact with the pin 167 at the descending end of the rotation path of the suction nozzle 16. , A cam 168 for regulating the position.
[0023]
Thereby, when the suction nozzle 16 turns upward as indicated by 16 'in FIG. 4, the distal end portion 16a is extended straight with the proximal end portion 16b by the bias of the spring 166, and is joined to each other. However, when the suction nozzle 16 pivots downward and is stored in the work carriage 8, the pin 167 is regulated by the cam 168 along with the pivot, and the arm of the spring 166 on the base end side portion 16 b side is drawn. 8, the spring 166 is bent in a V-shape against its own urging force, and the tip side portion 16a of the suction nozzle 16 is folded as shown.
[0024]
As shown in FIGS. 7 and 8, the tip of the suction nozzle 16 is bent downward in the drawing along the peripheral surface of the front top roller 24t located at a position raised and separated from the front bottom roller 24b, and heads toward the tip. And the width of the funnel is narrowed from both sides, and the suction port 164 is provided with the drawn yarn Y.Fiber bundleIn order to secure the maximum amount of intake air (intake area) while guiding to the center in the width direction of S (direction perpendicular to the running direction)Fiber bundleS has a flat elongated hole shape that is wide in the traveling direction of S and narrow in a direction perpendicular to the traveling direction. That is, the suction port 164 of the suction nozzle 16 passes the yarn end captured by the suction nozzle 16 through the draft device 2 on the upstream side of the front roller (reference roller) 24 of the draft device 2.Fiber bundleIt also serves as a yarn guide for guiding to the center in the width direction on the locus of S.
[0025]
At the ascending end of the orbit of the suction nozzle 16, the suction port 164 is located on the upstream side of the front top roller 24t, that is, above the tip of the middle top apron 23e, but above the middle top apron 23e. More surely the yarn Y sucked in 16Fiber bundleA yarn guide 30 for guiding the center of the S in the width direction is provided, and the suction port 164 of the suction nozzle 16 is located inside the yarn guide 30.
[0026]
As shown in FIG. 8, the thread guide 30 has an inverted isosceles triangular shape, and has a gutter-like shape in which the side plates 301, 301 are erected on both sides of a bottom plate 302 provided close to the middle top apron 23e, that is, on the isosceles. And is fixed to the draft cradle 29 by a bracket (not shown).
[0027]
The front end side of each side plate 301, that is, the front roller 24 side is formed in a wedge shape so as to be as close as possible to the front end of the middle apron 23e without contacting the front top roller 24t.
[0028]
On the other hand, the base end side of the suction nozzle 16 is rotatably connected to the suction pipe 17 via a joint 169 as shown in FIG. 1, and the other end of the suction pipe 17 is depressurized by a blower (not shown). It is connected to the dust box 20.
[0029]
The suction pipe 17 is formed in a U-shape along the back surface of the work vehicle 8 because a predetermined pipe length is required for the reason described later. In the vicinity of the junction of the suction pipe 17 with the suction nozzle 16, there is provided a yarn detection sensor 18 for detecting the end of the yarn Y passing through the portion, and on the pipe near the dust box 20 of the suction pipe 17. Is provided with a yarn cutting device 19 for cutting the drawn yarn Y.
[0030]
Next, the piecing process will be described based on the above embodiment. In the piecing process, a preparatory step of leading the yarn end Y on the take-up side to the draft device 2 as a pre-stage is performed.Fiber bundleThe process shifts to a piecing process in which S is joined.
[0031]
First, when the yarn clearer 6 detects a yarn defect or a yarn break (in the case of a yarn defect detection, the yarn is forcibly cut by a cutter (not shown) provided between the twisting device 4 and the delivery roller 5). 6, the back roller pair 21, the third roller pair 22, and the middle roller pair 23 of the draft device 2 are stopped,Fiber bundleThe supply of S is stopped. At this time, since the front roller pair 24 is still driven,Fiber bundleS is cut at the tip of the middle apron 23e, the yarn between the cut portion and the cut portion is sucked and removed by a duct (not shown), and the spun yarn Y downstream from the cut portion is taken up. It is wound around the package P of the device 7. During this time, the work cart 8 stops at the spinning unit 1u by another control signal output from the yarn clearer 6.
[0032]
Then, the air injection from the air spinning nozzle 3 is stopped by the work cart 8, the front top roller 24t is lifted up and away from the bottom roller 24b, and the air spinning nozzle 3 itself is also lifted up. It is separated from the delivery roller 5.
[0033]
Next, the package pressing plate 86 protrudes from the work carriage 8 based on the operation of the cam 88, advances between the package P and the friction roller 72, separates the package P from the friction roller 72, stops winding, and then grips. The lever 83 comes into contact with the cradle boss 74 to position the cradle arm 73 and the package P supported by the cradle arm 73 at a position separated from the friction roller 72. In this state, the suction mouth 9 rotates to bring its tip close to the package P and suck the yarn end.
[0034]
At the same time, after the turning arm 85 turns to press the reverse roller 84 against the package P, the suction mouth 9 cuts the spun yarn Y wound on the package P while rotating the package P in the reverse direction with the reverse roller 84. The yarn end is sucked and the yarn Y is pulled out upward. At this time, the thread removing guide 87 is placed so that the thread Y does not project and the thread Y does not catch on the traverse guide 71.
[0035]
Subsequently, as shown in FIG. 1, the yarn locking arm 101 and the yarn guiding arm 102 of the yarn guiding device 10 rotate respectively, and the yarn Y pulled out by the suction mouth 9 is locked by the yarn locking arm 101. At the same time, the yarn Y between the yarn locking arm 101 and the suction mouth 9 is locked to the yarn guide arm 102, and the yarn is fed backward by the yarn end guiding device 11 located at the descending end of the orbit. It is inserted into the nozzle 12. Next, after the thread Y is gripped by the clamp 14 (shown in FIG. 5), the cutter 13 is operated to cut the thread Y on the suction mouth 9 side and remove the thread Y by suction.
[0036]
During this time, the yarn Y of the package P is continuously rewound by the rotation of the reverse roller 84, whereby the excess yarn Y between the clamp 14 and the package P is once sucked into the slack tube 15.
[0037]
Then, from such a state, the clamp 14 and the yarn reversing nozzle 12 which grip the yarn end Y on the winding side by pivoting the yarn end guiding device 11 upward, and pneumatic spinning as described above. The yarn end Y is located at the outlet 32 of the nozzle 3 and guided to that position. At this time, the yarn Y previously sucked into the slack tube 15 is pulled out.
[0038]
In parallel with this, the suction nozzle 16 pivots upward, and its front end portion 16a is extended so that the suction port 164 of the front top roller 24t is lifted and separated from the bottom roller 24b as shown in FIG. It is located in the yarn guide 30 on the upstream side and above the middle top apron 23e, and suction at that part is started.
[0039]
Then, when air is injected in the yarn reverse feeding nozzle 12 from such a state, as shown in FIG. 5, an air flow from the yarn reverse feeding nozzle 12 to the middle apron 23e through the air spinning nozzle 3 is generated. Then, when the clamp 14 is opened, the yarn end Y is inserted into the air spinning nozzle 3 along the air flow. At this time, when the cause of the yarn breakage is a nozzle clogging of the air spinning nozzle 3, the fiber mass or the like clogged in the nozzle is blown off by the air flow and removed. Then, the yarn Y on the winding side inserted into the air spinning nozzle 3 is sucked into the suction nozzle 16, and the sucked yarn Y reaches the dust box 20 through the suction pipe 17 as shown in FIG. 6. Then, after reversing the predetermined length of the yarn Y, the reverse roller 84 returns to the original position, stops the rewinding of the yarn Y, and the yarn cutting device 19 cuts the yarn Y in the suction pipe 17 to cut the yarn Y. The finished yarn end is collected in the dust box 20.
[0040]
Next, the air spinning nozzle 3 is lowered to return to the original spinning position. By this operation, the yarn Y on the winding side is disengaged from the yarn reversing nozzle 12 (a slit for removing the yarn is formed in the yarn reversing nozzle 12), and a pair of rollers 41, 42 of the false twisting device 4 is provided. Introduced in between. At the same time, when the grip lever 83 is separated from the cradle boss 74, the package P is pressed against the friction roller 72, and the package P resumes the winding of the yarn Y, and is sucked into the suction pipe 17 with this. The drawn yarn Y is pulled out, and is accelerated to a normal winding speed while the yarn end reaches the yarn detection sensor 18.
[0041]
When the yarn detection sensor 18 provided at the end of the suction pipe 17 connected to the suction nozzle 16 detects passage of the yarn end, a detection signal is issued, whereby the control device 89 operates the spinning unit 1u in the following order. Is resumed and piecing is performed.
[0042]
That is, the clutch of the back roller 21, the third roller 22, and the middle roller 23 is closed at the same time when the yarn detection sensor 18 detects the passage of the yarn end.Fiber bundleAt the same time as the draft of S is restarted, the nip roller 51 is pressed against the delivery roller 5 to restart the feeding of the yarn Y, and immediately thereafter, the front top roller 24t is pressed against the front bottom roller 24b. Further, immediately thereafter, the supply of the compressed air to the air spinning nozzle 3 is restarted.
[0043]
Then, it stopped at the tip of the middle top apron 23e.Fiber bundleWhile S reaches the front roller pair 24 as shown in FIG. 8, the winding-side yarn end Y that has reached the suction port 164 of the suction nozzle 16 is flattened and expanded by the suction port 164 and the yarn guide 30. WasFiber bundleS is guided to the center in the width direction of S.Fiber bundleThe tip S and the yarn end Y on the take-up side are sent out from the front roller pair 24 in a state where they overlap with each other by a certain length, and are false twists given to the yarn Y on the take-up side by the false twisting device 4, and With the yarn end YFiber bundleS is twisted, and at this time, the yarn end YFiber bundleSince it is located at the center in the width direction of S, the yarn end YFiber bundleS is wrapped, bundled, joined and integrated.
[0044]
on the other hand,Fiber bundleThe fibers on both sides of the S tip are sucked into the air spinning nozzle 3 in a free state without being bundled, and are joined by the action of the swirling airflow in the air spinning nozzle 3 in the direction opposite to the false twist. Part and the focusing that follows itFiber bundleIs wound around the core to form a wound fiber.
[0045]
Further, through the false twist device 4,Fiber bundleWound fiber becomes the core in the process of untwisting false twistFiber bundleAs a result, the yarn end Y on the winding side and the fiber bundle S are pieced as one united spun yarn Y, and thereafter, the united spun yarn Y is continuously spun out.
[0046]
Since the part that has been pierced through the above-described process is integrated through the primary yarn forming process of the bundled spun yarn Y, it is structurally and apparently not different from other portions of the spun yarn Y. There is no change. Moreover, the yarn end Y on the winding side isFiber bundleSince the core is wrapped in the core by S, the yarn end Y does not jump out and a beautiful seam can be formed in appearance.
[0047]
In the above embodiment, the case where the fiber bundle is the sliver S is shown, but the fiber bundle may be a shin or the like other than the sliver. Further, in the above embodiment, the suction nozzle 16 is used as a yarn guide for guiding the yarn end captured by the suction nozzle 16 to the center in the width direction on the locus of the fiber bundle passing through the draft device upstream of the reference roller of the draft device. Although both the 16 suction ports 164 and the yarn guide 30 are provided, only one of them may be provided.
[0048]
Further, in the above-described embodiment, the case where the front roller pair 24 of the draft device 2 is used as a reference roller for piecing and the drive of the back roller pair 21, the third roller pair 22, and the middle roller pair 23 on the upstream side is stopped. However, it is also possible to stop driving only the back roller pair 21 or the back roller pair 21 and the third roller pair 22. In this case, the fiber bundle S is drafted, and the tip is the reference roller. It is necessary to advance the drive start timing for the time required to reach the front roller pair 24. In addition, the reference roller may be a middle roller pair 23 or a third roller pair 22, in which case a separation mechanism similar to that of the front roller pair 24 is provided. Further, in the above embodiment, the case where the twisting means is the false twisting device 4 including the air spinning nozzle 3 and the pair of rollers 41 and 42 is described, but the present invention is not limited to this, and the false twisting means is not limited to this. Other than this, for example, one in which a yarn guide tube in an air spinning nozzle is arranged, one in which two air spinning nozzles are arranged in series, further, a belt type, or a belt and roller , A disk type, and a combination of them and an air nozzle.
[0049]
【The invention's effect】
In the piecing method of the present invention, as described above, the spun yarn end is passed through the twisting means, pulled out to the reference roller upstream side of the draft device, and the yarn end is passed through the draft device.Fiber bundleIn order to operate the drafting device and the twisting means in the state guided in the width direction center on the locus ofFiber bundleIt is twisted so as to be wrapped in, and the appearance is not different from other parts, and the spliced fiber ends do not jump out of the seam and not only it is excellent in appearance but also has sufficient seam strength .
[0050]
Then, as a device for performing piecing, means for passing the spun yarn end from the downstream side of the twisting means to the upstream side of the reference roller of the draft device, and capturing the yarn end passed through the upstream side of the reference roller of the draft device And a yarn end captured by the yarn end capturing means passes through the draft device upstream of a reference roller of the draft device.Fiber bundleAnd a yarn guide that guides the yarn at the center in the width direction on the locus ofFiber bundleCan be reliably guided to the center in the width direction, and good piecing can be stably performed in both seam appearance and strength.
[0051]
Further, the yarn end catching means is a suction nozzle for sucking and catching the yarn end, and the suction port of the suction nozzle is formed in a flat shape narrowed in the width direction so as to also serve as a yarn guide, so that it can be used for piecing. To ensure that the spun yarn endsFiber bundleAnd a sufficient suction area is secured at the suction port, and the yarn end that has passed through the twisting means can be reliably sucked and drawn out to the reference roller upstream side.
[0052]
Since the yarn guide is provided fixed to the draft device, the position of the yarn guide is constant with respect to the reference roller of the draft device, and immediately before the spun yarn end reaches the nip point of the reference roller. In this case, the yarn end is prevented from swinging to the left and right due to the recoil of the yarn running, the yarn end can be reliably guided to the center of the fiber bundle, and good piecing in both appearance and strength can be stably performed.
[Brief description of the drawings]
FIG. 1 is a front view showing an example of a spinning machine for carrying out the method of the present invention.
FIG. 2 is a side sectional view showing an example of a spinning machine for carrying out the method of the present invention.
FIG. 3 is a sectional side view showing a main part of an example of a twisting device of a spinning machine for implementing the method of the present invention.
FIG. 4 is a side view showing a suction nozzle and its suction pipe.
FIG. 5 is a cross-sectional view of a main part showing a state where a yarn is inserted into a pneumatic spinning nozzle.
FIG. 6 is a side view showing a state where a yarn is sucked by a suction nozzle.
FIG. 7 is a side sectional view of a main part of the spinning machine during piecing.
FIG. 8 is a perspective view of a main part of the spinning machine during piecing.
[Explanation of symbols]
1 Spinning machine
2 Draft device
3 Pneumatic spinning nozzle
4 False twisting device
5 Delivery roller
6 Yarn clearer
7 Winding device
8 Work cart
9 Suction mouse
10 Yarn guide device
11 Yarn end guidance device
12 Yarn reverse feed nozzle
13 cutter
14 Clamp
15 Slack tube
16 Suction nozzle
17 Suction pipe
18 Yarn detection sensor
19 Yarn cutting device
20 dust box
24 Front roller pair (reference roller)
30 thread guide
SFiber bundle
Y spun yarn
P package

Claims (4)

The yarn drawn from the package is passed through the twisting means to the upstream side, and the yarn drawn to the upstream of the reference roller of the drafting device is held by the yarn end catching means. The operation of the spinning unit is resumed by detecting the passage of the yarn end by the yarn end detection means at a predetermined position in the yarn end capture means when the yarn end is pulled out from the capture means, and the yarn end twisting means is operated, whereby the yarn end is twisted. A piecing method in a spinning machine , wherein piecing is performed in a state where the fiber bundle and the fiber bundle are overlapped by a certain length . Means for passing the spun yarn end from downstream of the twisting means to the upstream of the reference roller of the draft device ; capturing the yarn end passed upstream of the reference roller of the draft device; A yarn end catching means having a yarn end detecting means at a long position, and a width direction center on a locus of a fiber bundle passing through the draft device at a position upstream of a reference roller of the draft device with the yarn end captured by the yarn end catching device. A piecing device for a spinning machine , comprising: a yarn guide for guiding the yarn end portion; and a control device for controlling a draft device and a twisting device based on a yarn end detection result by the yarn end detection device. The yarn end catching means is a suction nozzle for sucking and catching a yarn end, and the suction port of the suction nozzle is formed in a flat shape narrowed in a width direction so as to also serve as a yarn guide. 3. A piecing device in the spinning machine according to 2. The piecing device according to claim 2, wherein the yarn guide is fixed to the draft device.

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