CN104925584B

CN104925584B - Yarn winding machine and winding method

Info

Publication number: CN104925584B
Application number: CN201510113195.5A
Authority: CN
Inventors: 牟田胜文
Original assignee: Murata Machinery Ltd
Current assignee: Murata Machinery Ltd
Priority date: 2014-03-19
Filing date: 2015-03-16
Publication date: 2021-02-05
Anticipated expiration: 2035-03-16
Also published as: IN2015DE00296A; DE102015204302A1; JP2015178403A; CN104925584A

Abstract

The invention provides a yarn winding machine and a winding method. An automatic winder (1) is provided with a traverse arm (71) and a unit control unit (51). The traverse arm (71) traverses the yarn (20) wound around the tapered package (30). When the winding stage advances, the unit control section (51) increases the ratio of the traverse speed of the traverse arm (71) in the small diameter side region to the traverse speed of the traverse arm (71) in the large diameter side region, i.e., the traverse speed ratio.

Description

Yarn winding machine and winding method

Technical Field

The present invention relates to a yarn winding machine that winds a yarn while traversing the yarn to form a tapered package.

Background

Conventionally, in a yarn winding machine that winds a tapered package, control is performed such that the traverse speed in the large diameter side region of the package is smaller than the traverse speed in the small diameter side region. By performing this control, the shape of the package can be appropriately formed, the winding density in the large diameter side region can be increased, and the unwinding property of the package can be improved. In the following description, the ratio of the traverse speed in the small diameter side region to the traverse speed in the large diameter side region is referred to as a traverse speed ratio. German patent application publication No. 102008015907 (patent document 1) and japanese patent application laid-open No. 2012 and 017205 (patent document 2) disclose yarn winding machines capable of setting a traverse speed ratio.

Patent document 1 discloses a technique for reducing the traverse speed ratio in accordance with the progress of the winding stage. Patent document 2 discloses a technique of adjusting a velocity profile for each of a small diameter region and a large diameter region when a traverse speed ratio (lay length ratio) is set. The velocity profile includes information such as traverse time, traverse speed, acceleration time of the traverse guide, and acceleration of the traverse guide.

When a conical package is formed, a phenomenon (flange winding) may occur in which an end surface of the package bulges out, particularly on the smaller diameter side. This phenomenon is caused by the yarn layer in the middle portion of the package protruding from the end face of the package by being pressed by the tightening force of the yarn on the outer diameter side and the repulsive force from the winding tube. The occurrence of the convex winding cannot be prevented in some cases only by setting a gradually decreasing or constant traverse speed ratio as in the conventional case.

In particular, in the case of forming a package with a high winding density or winding a thick yarn to form a package (that is, in the case of a high tension), the bulge winding is likely to occur.

Conventionally, in order to prevent the occurrence of the convex winding, control for adjusting the traverse width or the winding angle is performed. However, setting of these controls is easily complicated. In the above control, the traverse width and/or the winding angle are adjusted by an appropriate amount in order to suppress the occurrence of the convex winding. As a result, there are problems such as an increase in package size and difficulty in handling.

Disclosure of Invention

The invention aims to provide a yarn winding machine which can prevent the generation of convex edge winding through simple setting and can restrain the increase of package size.

According to a first aspect of the present invention, a yarn winding machine includes a traverse guide and a control section. The traverse guide traverses the yarn wound around the tapered package. The control section controls at least the traverse speed of the traverse guide. The ratio of the traverse speed of the traverse guide in the small diameter side region to the traverse speed of the traverse guide in the large diameter side region is referred to as a traverse speed ratio. When the winding stage is advanced, the control section increases the traverse speed ratio.

In the conventional control for adjusting the traverse width, the traverse width is directly reduced. In the control for adjusting the winding angle, the winding density is reduced. In the control of the present embodiment, the balance of the winding densities of the small-diameter side region and the large-diameter side region is changed. Therefore, an increase in package size can be suppressed. Further, the occurrence of the winding of the bead can be prevented by a simple process as compared with the conventional control.

In the above-described yarn winding machine, it is preferable that the control section continuously increases the traverse speed ratio in accordance with the progress of the winding stage.

This makes it possible to increase the initial winding density of the small-diameter side region and the winding density of the intermediate yarn layer, and thus reliably prevent the occurrence of bulge winding.

In the yarn winding machine, it is preferable that the control section increases the traverse speed ratio in accordance with an increase in the thickness of the yarn layer of the package or the package diameter.

Accordingly, the traverse speed ratio is closely related to the thickness of the yarn layer or the package diameter, and therefore the occurrence of the winding of the raised edge can be appropriately prevented.

The yarn winding machine described above preferably includes a setting unit capable of setting the starting traverse speed ratio, the final traverse speed ratio, and the switching threshold value. The starting traverse speed ratio is the traverse speed ratio applied at the start of winding of the package. The final traverse speed ratio is an upper limit of the applied traverse speed ratio. The switching threshold defines a timing of switching to the final traverse speed ratio.

This makes setting easier than control for changing the traverse width or the winding angle, and thus reduces the labor of the operator.

The yarn winding machine preferably further includes an acquiring unit that acquires the thickness of the yarn layer or the package diameter. When the yarn layer thickness or the package diameter acquired by the acquisition section is smaller than the switching threshold, the control section controls the traverse guide using a target traverse speed ratio determined based on at least the starting traverse speed ratio and the final traverse speed ratio.

This can increase the winding density in the small diameter side region at the initial stage of winding, and thus can prevent the occurrence of the convex winding.

In the yarn winding machine, it is preferable that: when the yarn layer thickness or the package diameter acquired by the acquisition section is larger than the switching threshold, the control section controls the traverse guide using the final traverse speed ratio.

Accordingly, if the winding stage is advanced to some extent, the occurrence of the convex winding can be prevented without adjusting the winding density in the small diameter side region, and therefore, the winding density in the small diameter side region can be prevented from being excessively reduced.

In the yarn winding machine, the control unit preferably changes the winding angle in accordance with the winding stage.

This can more reliably prevent the occurrence of the convex edge winding.

In the above yarn winding machine, the control section preferably changes the traverse width of the traverse guide in accordance with the winding stage.

This can more reliably prevent the occurrence of the convex edge winding.

According to a second aspect of the present invention, the following winding method is provided. That is, the winding method includes an acquisition step, an evaluation step, and a control step. In the obtaining step, the thickness of the yarn layer or the package diameter of the package is obtained. In the evaluation step, a traverse speed ratio, which is a ratio of the traverse speed of the traverse guide in the small diameter side region to the traverse speed of the traverse guide in the large diameter side region, is determined based on the yarn layer thickness or the package diameter acquired in the acquisition step. In the control step, the traverse guide is controlled at the traverse speed ratio determined in the evaluation step.

This can suppress an increase in package size.

Drawings

Fig. 1 is a front view of an automatic winder according to an embodiment of the present invention.

Fig. 2 is a front view and a block diagram of the yarn winding unit.

Fig. 3A is a flowchart illustrating a process of changing the traverse speed ratio.

Fig. 3B is a formula for calculating the target traverse speed ratio.

Fig. 4A is a table showing setting items when the traverse speed ratio is changed.

Fig. 4B is a diagram showing a change in the traverse speed ratio with an increase in the thickness of the yarn layer.

Fig. 5 is a schematic front view of the winding unit for explaining the winding angle.

Fig. 6 is a diagram showing an example of setting the winding angle.

Fig. 7 is a diagram illustrating control for changing the traverse width.

Fig. 8A and 8B are diagrams illustrating changes in the traverse speed ratio according to the modification with an increase in the thickness of the yarn layer.

Detailed Description

Next, an embodiment of the present invention will be described with reference to the drawings. In the present specification, "upstream" and "downstream" mean upstream and downstream in the running direction of the yarn at the time of winding the yarn.

As shown in fig. 1, an automatic winder (yarn winding machine) 1 includes a plurality of yarn winding units 10, a doffing device 60, and a machine body control device 90, which are arranged side by side.

Each yarn winding unit 10 winds the yarn 20 unwound from the yarn feeding bobbin 21 around a tapered winding tube 22 supported by a cradle 23 while traversing the yarn to form a package 30. Further, the cradle 23 has: a small-diameter side support portion for rotatably supporting the small-diameter side end of the take-up tube 22; and a large-diameter side support portion for rotatably supporting the large-diameter side end portion of the take-up tube 22.

The doffing device 60 moves to the position of the yarn winding unit 10 when the package 30 is fully wound in each yarn winding unit 10. The doffer 60 removes the fully wound package 30 from the cradle 23 in the yarn winding unit 10, and supplies the winding tube 22 (empty bobbin) around which the yarn 20 has not been wound.

The body control device 90 includes a body setting unit (setting unit) 91 and a body display unit 92. The body setting unit 91 can perform setting for each yarn winding unit 10 by an operator inputting a predetermined set value or selecting an appropriate control method. The body display unit 92 can display the winding state of the yarn 20 in each yarn winding unit 10, the contents of the generated failure, and the like.

Next, the structure of the yarn winding unit 10 will be specifically described with reference to fig. 2.

Each yarn winding unit 10 includes a winding unit main body 17 and a unit control unit 51.

The Unit control Unit 51 includes, for example, a Central Processing Unit (CPU), a Random Access Memory (RAM), a Read Only Memory (ROM), an Input-and-Output (I/O) port, and a communication port. The ROM stores a program for controlling each part of the winding unit main body 17. The I/O port and the communication port are connected to each unit provided in the winding unit main body 17 and the machine body control device 90, and communication of control information and the like is possible. Thus, the unit control section 51 can control the operation of each section provided in the winding unit main body 17.

In the winding unit main body 17, in the yarn running path between the yarn supplying bobbin 21 and the contact roller 29, the yarn unwinding assisting device 12, the tension applying device 13, the splicing device 14, the yarn length detecting sensor 15, the yarn clearer 16, and the winding unit 18 are arranged in this order from the yarn supplying bobbin 21 side.

The yarn unwinding assisting device 12 assists unwinding of the yarn 20 from the yarn supply bobbin 21 by lowering the regulating member 40 covering the core tube of the yarn supply bobbin 21 in conjunction with unwinding of the yarn 20 from the yarn supply bobbin 21. The regulating member 40 is in contact with a balloon formed on the upper portion of the yarn feeding bobbin 21 by the rotation of the yarn 20 unwound from the yarn feeding bobbin 21 and the centrifugal force, and assists the unwinding of the yarn 20 by controlling the balloon to an appropriate size. A sensor, not shown, for detecting the upper tapered face portion of the yarn feeding bobbin 21 is provided in the vicinity of the regulating member 40. When the sensor detects the lowering of the upper tapered surface portion of the cop, the regulating member 40 is lowered by, for example, an air cylinder (not shown).

The tension applying device 13 applies a predetermined tension to the running yarn 20. As the tension applying device 13, for example, a gate type in which movable comb teeth are arranged with respect to fixed comb teeth can be used. The movable comb teeth can be rotated by a rotary solenoid so that the comb teeth are engaged with each other or disengaged from each other. The tension applying device 13 may be a disk type, for example, in addition to the gate type.

The yarn splicing device 14 splices the lower yarn on the yarn feeding bobbin 21 side and the upper yarn on the package 30 side when the yarn clearer 16 detects a yarn defect and cuts the yarn, or when the yarn breaks during unwinding from the yarn feeding bobbin 21. The joint device 14 may be of a mechanical type or a structure using a fluid such as compressed air.

The yarn length detection sensor 15 detects the yarn length of the yarn 20 wound in the package 30 in a non-contact manner. The yarn length detection sensor 15 detects the amount of hairiness of the yarn 20, calculates the amount of movement of the yarn 20, and detects the yarn length. Specifically, the yarn length detection sensor 15 includes a plurality of optical hairiness detection portions each having a light receiving element and a light source along the yarn traveling direction. The yarn length detection sensor 15 detects the running length of the yarn 20 based on changes in the output signals of the plural hairiness detection portions at different positions in the yarn running direction.

The unit control section (acquisition section) 51 can determine the thickness of the yarn layer of the package 30 using the running length of the yarn 20 detected by the yarn length detection sensor 15. Specifically, the unit control section 51 can calculate the winding angle from the yarn running speed calculated based on the running length detected by the yarn length detection sensor 15 and the traverse speed. The unit control section 51 calculates the package diameter based on the winding angle, the circumferential speed of the package 30, and the rotation speed of the package 30. The unit control section 51 can calculate the yarn layer thickness by subtracting the diameter of the winding tube 22 from the package diameter.

The yarn clearer 16 includes: a clearer head 49 provided with an unillustrated sensor for detecting the thickness of the yarn 20; and an analyzer 52 for processing the yarn thickness signal from the sensor. The yarn clearer 16 detects a yarn defect such as a slub yarn by monitoring a yarn thickness signal from the sensor. A cutter, not shown, is provided near the yarn clearer head 49 to cut the yarn 20 immediately when the yarn clearer 16 detects a yarn defect.

The lower yarn catching member 25 is provided below the yarn splicing device 14, and catches and guides the yarn end of the lower yarn on the yarn feeding bobbin 21 side to the yarn splicing device 14. The lower yarn catching member 25 includes: a lower yarn bobbin arm 33; and a lower yarn suction port 32 formed at the front end of the lower yarn tubular arm 33.

The upper yarn catching member 26 is provided above the yarn splicing device 14, and catches and guides the yarn end of the upper yarn on the package 30 side to the yarn splicing device 14. The upper yarn catching member 26 includes: an upper yarn bobbin arm 36; and an upper yarn suction port 35 formed at the front end of the upper yarn bobbin arm 36.

Lower bobbin arm 33 and upper bobbin arm 36 are rotatable about

shafts

34 and 37, respectively. A suitable negative pressure source (not shown) is connected to each of the lower yarn bobbin arm 33 and the upper yarn bobbin arm 36. Accordingly, the lower yarn suction port 32 and the upper yarn suction port 35 are caused to generate a suction air flow, and the yarn ends of the upper yarn and the lower yarn can be sucked and caught by the lower yarn bobbin arm 33 and the upper yarn bobbin arm 36, respectively.

The winding unit 18 includes: a cradle 23 for detachably supporting the take-up tube 22; a contact roller 29 that is rotatable while being in contact with the outer peripheral surface of the winding tube 22 or the outer peripheral surface of the package 30; a traverse arm (traverse guide) 71; and a traverse drive motor 72.

The cradle 23 can rotate about the rotation shaft 48. The cradle 23 can rotate to absorb an increase in the thickness of the yarn layer accompanying the winding of the yarn 20 into the winding tube 22.

A package driving motor 41 is attached to the cradle 23. The winding tube 22 is rotationally driven by the package driving motor 41, and the yarn 20 is wound around the winding tube 22. When the winding tube 22 is supported by the cradle 23, the motor shaft of the package driving motor 41 and the winding tube 22 are connected so as not to be relatively rotatable (so-called direct drive method). The operation of the package driving motor 41 is controlled by the package driving control section 42. The package drive control unit 42 receives an instruction from the unit control unit 51 to adjust the rotation speed (or the acceleration) of the package drive motor 41.

The traverse arm 71 traverses the yarn 20 while guiding the yarn 20. The traverse arm 71 is driven by a traverse drive motor 72. Specifically, the traverse arm 71 is provided to continuously reciprocate in conjunction with the forward and reverse rotation of the rotor of the traverse drive motor 72. The operation of the traverse drive motor 72 is controlled by the unit control section 51 via the traverse drive control section 73. A hook-shaped yarn guide section, for example, is formed at the distal end of the traverse arm 71. The traverse arm 71 performs reciprocating rotational motion while the yarn 20 is held (guided) by the yarn guide section, thereby enabling the yarn 20 to traverse. Further, a guide plate 28 is provided slightly upstream of the traverse position. The guide plate 28 guides the yarn 20 on the upstream side to the traverse position.

Next, control in which the unit control section 51 changes the traverse speed ratio in accordance with an increase in the thickness of the yarn layer will be described with reference to fig. 3A to 4B. The traverse speed ratio is a ratio of the traverse speed in the small diameter region to the traverse speed in the large diameter region. Since the traverse time in the large diameter side region of the package also has the same value as the traverse time in the small diameter side region, this value also corresponds to the traverse speed ratio.

First, the contents of this control will be explained. In this control, as shown in fig. 4B, the traverse speed ratio is gradually increased from the start of the winding operation to a predetermined time. After a predetermined time (switching of the yarn layer thickness) has elapsed, the traverse speed ratio is kept constant.

As shown in patent documents 1 and 2, conventionally, since the traverse speed ratio is made constant or gradually decreased, the winding density in the small diameter side region is greatly increased (the winding density of the yarn layer in the initial and intermediate portions is low) with an increase in the thickness of the yarn layer. As a result, a convex edge winding is generated. In contrast, in the present embodiment, since the traverse speed ratio is gradually increased, the increase in the winding density in the small diameter side region (which may be constant or small) associated with the increase in the yarn layer thickness can be suppressed. Therefore, the occurrence of the winding of the convex edge can be prevented.

In the case of this control, the operator sets the starting traverse speed ratio, the final traverse speed ratio, and the switching yarn layer thickness to the machine body setting portion 91 before the winding operation is started (see fig. 4A). The start traverse speed ratio is a traverse speed ratio applied at the start of winding of the package 30. When the initial traverse speed ratio is small, the occurrence of the convex winding is easily prevented, but the yarn falling on the large diameter side is easily caused. Therefore, in consideration of the above, it is necessary to determine a value for starting the traverse speed ratio. The final traverse speed ratio refers to the upper limit of the applied traverse speed ratio. The switching yarn layer thickness (switching threshold) is a value (yarn layer thickness) that defines the timing of switching to the final traverse speed ratio. The body control device 90 transmits an instruction of the operator to the unit control unit 51 of each yarn winding unit 10. The unit control unit 51 receives the setting value received from the body control device 90 (step S101).

Thereafter, winding of the package 30 is started, and the unit control section 51 controls the traverse driving motor 72 so that the traverse arm 71 traverses the yarn 20 at the start of the traverse speed ratio. After that, when determining that the winding of the package 30 is underway (step S102), the unit control section 51 determines whether or not the current yarn layer thickness is smaller than the switching yarn layer thickness (step S103). The current yarn layer thickness can be calculated (obtained) based on the detection result of the yarn length detection sensor 15 as described above.

When determining that the current yarn layer thickness is smaller than the switching yarn layer thickness, the unit control section 51 calculates the target traverse speed ratio (step S104). The target traverse speed ratio is calculated using the formula (1) shown in fig. 3B. In the present embodiment, since the target traverse speed ratio is linear, the slope can be calculated by dividing the value obtained by subtracting the starting traverse speed ratio from the final traverse speed ratio by the switched yarn layer thickness. The target traverse speed ratio can be calculated by adding an initial value, i.e., a starting traverse speed ratio, to a value obtained by multiplying the slope by the thickness of the current yarn layer.

The unit control section 51 controls the traverse driving motor 72 so that the yarn 20 is traversed at the target traverse speed ratio calculated as described above by the traverse arm 71 (step S105). Next, the unit control section 51 performs the process of step S102 again. When the unit control section 51 calculates the target traverse speed ratio again, the current yarn layer thickness increases, and therefore the target traverse speed ratio also increases. In this way, the unit control section 51 performs control to gradually increase the traverse speed ratio in accordance with an increase in the thickness of the yarn layer.

Then, when the current yarn layer thickness becomes equal to or larger than the switching yarn layer thickness as the winding stage proceeds (when no is determined in step S103), the unit control section 51 sets the target traverse speed ratio to the final traverse speed ratio (step S106), and controls the traverse driving motor 72 so that the yarn 20 is traversed at the traverse speed ratio by the traverse arm 71 (step S105). The unit control section 51 ends the control of gradually increasing the traverse speed ratio in accordance with the increase in the thickness of the yarn layer, and transitions to the control of operating the traverse arm 71 at a constant traverse speed ratio.

Until the winding of the package 30 is completed (until no determination is made in step S102), the unit control section 51 controls the traverse driving motor 72 to traverse the yarn 20 at the final traverse speed ratio by the traverse arm 71.

In this way, the yarn winding unit 10 can control the traverse speed ratio to be changed only by setting the three setting items by the operator. Thus, the occurrence of the convex edge winding can be prevented by a simple process. In particular, in the present embodiment, since the traverse speed ratio is changed according to the thickness of the yarn layer and the thickness of the yarn layer is not dependent on the position in the winding width direction, the measurement can be performed easily and accurately. Therefore, the traverse speed ratio can be controlled with high accuracy.

Further, the occurrence of the convex winding can be prevented only by changing the traverse speed ratio in the above-described manner. However, when the package 30 having a high winding density is formed, or when the package 30 is formed with the thick yarn 20, the bulge winding is likely to occur as described above. Therefore, in order to reliably prevent the occurrence of the convex winding, it is also possible to perform control for adjusting the winding angle and/or control for adjusting the traverse width simultaneously with control for changing the traverse speed ratio.

The control for adjusting the winding angle will be described with reference to fig. 5 and 6. As shown in fig. 5, the winding angle θ is an inclination angle of the yarn 20 on the package 30 with respect to a vertical line of the axis of the winding tube 22. The crossing angle of the yarn 20 and the yarn 20 may be treated as a winding angle.

Although the method of setting the winding angle is arbitrary, for example, there is a method of designating a plurality of points (black points in fig. 6) by associating the thickness of the yarn layer with the winding angle and connecting the designated points. As described above, since the bulge winding is a phenomenon in which the yarn layer on the outer side receives a pressure and the yarn layer on the middle portion protrudes from the end face of the package 30, the bulge winding can be prevented by increasing the winding angle of the portion corresponding to the yarn layer on the middle portion.

Next, control for adjusting the traverse width will be described with reference to fig. 7.

Although the method of setting the correction width (correction length) of the traverse width is arbitrary, for example, there is a method of designating a plurality of points (black points in fig. 7) by associating the thickness of the yarn layer with the correction width and connecting the designated plurality of points. By increasing the correction width of the portion corresponding to the yarn layer in the middle portion, the occurrence of the winding of the raised edge can be prevented.

As shown in fig. 7, the traverse width correction width can be set to have different values on the small diameter side and the large diameter side. Since the small diameter side is likely to cause the burring, the generation of the burring can be more reliably prevented by increasing the correction width than the large diameter side.

As described above, the automatic winder 1 according to the present embodiment includes the traverse arm 71 and the unit control unit 51. The traverse arm 71 traverses the yarn 20 wound around the tapered package 30. The unit control section 51 increases the traverse speed ratio when the winding stage progresses.

In conventional control for adjusting the traverse width or the winding angle, the winding width (traverse width) is directly reduced or the winding density is reduced. In the control of the present embodiment, only the balance of the winding densities of the small diameter side region and the large diameter side region is changed. Therefore, an increase in package size can be suppressed. Further, the occurrence of the winding of the bead can be prevented by a simple process as compared with the conventional control.

The automatic winder 1 of the present embodiment includes a body setting unit 91 capable of setting a starting traverse speed ratio, a final traverse speed ratio, and a switching threshold.

Next, a modification of the above embodiment will be described with reference to fig. 8A and 8B.

In the above embodiment, a mode is applied in which the traverse speed ratio is continuously changed in accordance with the thickness of the yarn layer, and then the traverse speed ratio is made constant. However, any mode can be used as long as the traverse speed ratio is increased according to the increase in the thickness of the yarn layer.

For example, as shown in fig. 8A, the traverse speed ratio may be changed stepwise. In this case, when the yarn layer thickness becomes equal to or greater than a predetermined reference value, the unit control section 51 increases the traverse speed ratio by one step. In this case, since it is not necessary to always calculate the target traverse speed ratio, the amount of processing of the unit control section 51 can be suppressed.

As shown in fig. 8B, the traverse speed ratio may be continuously changed without setting a region in which the traverse speed ratio is constant. The traverse speed ratio may be changed in any manner, and is not limited to a linear or stepwise manner, and may be changed in a curve, for example.

Although the preferred embodiment and the modified examples of the present invention have been described above, the above configuration can be modified as follows, for example.

In the above embodiment, the unit control section 51 performs control for changing the traverse speed ratio, but a part or all of the control may be performed by the body control device 90 or the traverse drive control section 73.

The traverse guide is not limited to the arm-type traverse guide as in the above-described embodiment, and may be a belt-type traverse guide, for example.

Instead of directly rotating the package 30 by the package driving motor 41, the package 30 may be driven to rotate by the rotation of the contact roller 29.

As a configuration for determining the thickness of the yarn layer of the package 30, an angle sensor for detecting the angle of the cradle 23 (the rotation angle about the rotation axis 48) may be used. The angle sensor is constituted by, for example, a rotary encoder, and transmits an angle signal corresponding to the angle of the cradle 23 to the unit control unit 51. Since the angle of the cradle 23 changes as the winding operation of the package 30 progresses, the package diameter can be detected by detecting the angle using the angle sensor. The thickness of the yarn layer of the package 30 can be calculated by subtracting the diameter of the winding tube 22 from the package diameter. As a method of detecting the thickness of the yarn layer, an appropriate structure such as an analog sensor or an absolute sensor may be used in addition to the angle sensor.

As a structure for determining the thickness of the yarn layer of the package 30, a timer capable of measuring the elapsed time can be used. In this case, the temporal change in the thickness of the yarn layer is determined in advance by calculation or an empirical value based on the winding conditions. Then, the thickness of the yarn layer is determined based on the determined value and the measured elapsed time. The timer can measure the elapsed time considering the time of the winding interruption due to the yarn cutting and the yarn breakage.

In the above embodiment, the traverse speed ratio is changed according to the thickness of the yarn layer, but any configuration may be adopted as long as the traverse speed ratio is changed according to the winding stage, and a configuration using items other than the thickness of the yarn layer may be adopted. For example, instead of the yarn layer thickness, the package diameter, the length of the yarn 20 already wound (yarn length), the winding time, or the like may be used. In this case, the switching threshold value is a package diameter, a yarn length, or a winding time, instead of the yarn layer thickness.

In the above description, the operator sets the starting traverse speed ratio, the final traverse speed ratio, and the switching yarn layer thickness, but may set the slope, for example. Further, the correspondence relationship between the yarn layer thickness and the traverse speed ratio at a plurality of points may be specified, and the specified plurality of points may be connected. In other words, a plurality of switching traverse speed ratios may be provided between the starting traverse speed ratio and the final traverse speed ratio.

The present invention is not limited to an automatic winder, and can be applied to other yarn winding machines such as a beam winder and a spinning machine (for example, an air spinning machine and a free end spinning machine).

Claims

1. A yarn winding machine which winds a yarn unwound from a yarn supplying bobbin around a tapered winding tube supported by a cradle while traversing the yarn, thereby forming a tapered package, the cradle comprising: a small-diameter side support portion rotatably supporting a small-diameter side end portion of the take-up tube; and a large-diameter side support portion rotatably supporting a large-diameter side end portion of the take-up tube, the large-diameter side support portion including:

a traverse guide that traverses the yarn wound around the conical package; and

a control section for controlling at least the traverse speed of the traverse guide,

when the ratio of the traverse speed of the traverse guide in the small diameter side region to the traverse speed of the traverse guide in the large diameter side region is referred to as a traverse speed ratio,

the control unit increases the traverse speed ratio when the winding stage is advanced.

2. The yarn winding machine of claim 1,

the control unit continuously increases the traverse speed ratio in accordance with the progress of the winding stage.

3. The yarn winding machine of claim 1,

the control section increases the traverse speed ratio in accordance with an increase in the thickness of the yarn layer of the package or the package diameter.

4. The yarn winding machine of claim 2,

5. The yarn winding machine as claimed in claim 3,

the device includes a setting unit capable of setting:

the traverse speed ratio applied at the start of winding of the package, i.e., a start traverse speed ratio;

the upper limit of the applied traverse speed ratio, i.e., the final traverse speed ratio; and

a switching threshold value for timing of switching to the final traverse speed ratio is defined.

6. The yarn winding machine as claimed in claim 4,

the device includes a setting unit capable of setting:

7. Yarn winding machine according to claim 5,

further comprising an acquisition unit for acquiring the yarn layer thickness or the package diameter,

when the yarn layer thickness or the package diameter acquired by the acquisition section is smaller than the switching threshold, the control section controls the traverse guide using a target traverse speed ratio determined based on at least the starting traverse speed ratio and the final traverse speed ratio.

8. The yarn winding machine of claim 6,

9. The yarn winding machine of claim 7,

the control section controls the traverse guide using the final traverse speed ratio when the yarn layer thickness or the package diameter acquired by the acquisition section is larger than the switching threshold.

10. The yarn winding machine of claim 8,

11. The yarn winding machine according to any one of claims 1 to 10,

the control unit changes the winding angle in accordance with the winding stage.

12. The yarn winding machine according to any one of claims 1 to 10,

the control section changes the traverse width of the traverse guide in accordance with the winding stage.

13. The yarn winding machine of claim 11,

14. A winding method used in a yarn winding machine that winds a yarn unwound from a yarn supplying bobbin around a tapered winding bobbin supported by a cradle while traversing the yarn, thereby forming a tapered package, the cradle comprising: a small-diameter side support portion rotatably supporting a small-diameter side end portion of the take-up tube; and a large-diameter side support portion rotatably supporting a large-diameter side end portion of the take-up tube, the large-diameter side support portion including:

an obtaining step of obtaining a yarn layer thickness or a package diameter of the package in a tapered shape;

an evaluation step of determining a traverse speed ratio, which is a ratio of a traverse speed in a small diameter side region of a traverse guide for traversing a yarn wound in the package to a traverse speed in a large diameter side region of the traverse guide, based on the yarn layer thickness or the package diameter acquired in the acquisition step; and

and a control step of controlling the traverse guide at the traverse speed ratio obtained in the evaluation step, and increasing the traverse speed ratio when the winding step advances.