CN112209171B

CN112209171B - Yarn winding machine and yarn winding method

Info

Publication number: CN112209171B
Application number: CN202010540868.6A
Authority: CN
Inventors: 寺尾雄帆
Original assignee: Murata Machinery Ltd
Current assignee: Murata Machinery Ltd
Priority date: 2019-07-09
Filing date: 2020-06-15
Publication date: 2024-03-19
Anticipated expiration: 2040-06-15
Also published as: JP2021011377A; CN112209171A; TR202010270A2

Abstract

The present invention relates to a yarn winding machine and a yarn winding method. In an automatic winder (1), when a package (P) is stopped before a winding drum (42), a unit control unit (14) controls a movement mechanism (45) so that the package (P) is brought into contact with the winding drum (42) before the winding drum (42) stops rotating at a timing when the circumferential speed of the winding drum (42) is equal to or lower than a predetermined reference circumferential speed.

Description

Yarn winding machine and yarn winding method

Technical Field

The present invention relates to a yarn winding machine and a yarn winding method.

Background

In an automatic winder (yarn winding machine) disclosed in japanese patent application laid-open publication 2016-50060, a plurality of yarn winding units wind a traveling yarn while traversing the yarn while bringing the package into contact with a winding drum rotating in a predetermined direction (in normal rotation) and rotating the package in a driven manner. When the advancing yarn breaks for some reason, the yarn winding unit is spliced by the splicing device. The package is separated from the take-up drum by a lifting mechanism before the splicing, and the rotation is stopped independently of each other. This can prevent damage to the surface of the package due to contact (scraping) with the winding drum before stopping, and can stop the rotation of the package and the winding drum promptly. At this time, the yarn on the package side of the broken yarn is temporarily wound around the package. Then, the yarn winding unit brings the package into contact with the winding drum again, and then, the yarn end of the yarn wound around the package is caught by the upper yarn catching member while reversing the package, and the yarn end is guided to the yarn splicing device.

Here, when the package and the winding drum are stopped from rotating, if the package is stopped before the winding drum, the yarn end may hang down from the package after the rotation is stopped and be wound around the winding drum before the rotation is stopped. As a result, the yarn may be wound into a space different from the traveling space of the yarn at the time of normal yarn winding (specifically, a space on the opposite side of the traveling space with the winding drum interposed therebetween).

When the yarn splicing is performed in this state, the yarn winding process is restarted in a state in which an abnormal yarn path is formed, and therefore, the traverse cannot be performed normally, and the like, resulting in a defective shape of the package. In order to avoid such a problem, it is conceivable to wind the hanging yarn end into the package again by bringing the package and the winding drum into contact with each other again after stopping the rotation of the package and, for example, by rotating the winding drum further forward to rotate the package in a driven manner (japanese patent application laid-open No. 2007-302457).

As described in japanese patent application laid-open No. 2007-302457, when the winding drum is rotated further after the rotation of the package and the winding drum is stopped to rotate the package, the time from the yarn breakage to the splicing becomes long, and the production efficiency is lowered.

Disclosure of Invention

The purpose of the present invention is to prevent the yarn end of a broken yarn from being wound into a winding drum while avoiding the long time from yarn breakage to yarn joining.

The yarn winding machine according to claim 1 includes: a yarn feeding unit configured to feed yarn; a winding unit configured to perform a winding process of winding the yarn supplied from the yarn supplying unit on a winding bobbin to form a package; and a yarn joining mechanism for joining the yarn broken between the yarn feeding portion and the winding portion in a yarn traveling direction, wherein the winding portion includes: a cradle for rotatably supporting the package; a winding drum which rotates in contact with the package to thereby rotate the package; a drum driving unit for rotationally driving the winding drum; a braking unit for braking the rotation of the package; and a switching mechanism configured to switch a state of the winding unit between a contact state in which the package and the winding drum are in contact with each other and a separation state in which the package and the winding drum are separated from each other, wherein the yarn winding machine includes a control unit configured to control the switching mechanism to separate the package from the winding drum before the yarn is spliced by the splicing mechanism during the winding process, and further to control the drum driving unit to stop rotation of the winding drum and to control the braking unit to stop rotation of the package, and wherein the switching mechanism is configured to control the switching mechanism to bring the package into contact with the winding drum again before the winding drum stops rotating when a circumferential speed of the winding drum is equal to or lower than a predetermined reference circumferential speed when the package is stopped before the winding drum stops rotating.

In the present invention, the package, which has stopped rotating, comes into contact with the winding drum before stopping rotating again at a timing when the circumferential speed of the winding drum becomes equal to or lower than the reference circumferential speed. This can prevent damage to the surface of the package due to scraping from the winding drum, and can rotate the package again by the time the winding drum stops rotating. Therefore, even when the yarn end temporarily hangs down from the package, the yarn can be wound again around the package, and the winding drum can be directly stopped. Thus, the broken yarn ends can be prevented from being wound into the winding drum.

Further, since the package is brought into contact with the winding drum before the rotation is stopped in this manner, it is not necessary to additionally rotate the winding drum after the rotation of the winding drum is stopped, and the splicing can be started promptly. Thus, the time required for the splicing operation can be reduced as compared with the case where the winding drum is additionally rotated.

As described above, it is possible to prevent the yarn end of the broken yarn from being wound into the winding drum while avoiding a long time from the yarn breaking to the yarn joining.

In the yarn winding machine according to claim 2, in claim 1, a traverse groove for traversing the yarn is formed in an outer peripheral surface of the winding drum.

In the structure of traversing the yarn along the traverse groove, when an abnormal yarn path is formed after the yarn is spliced by the yarn end hanging from the package being wound into the winding drum, the yarn is wound around the package without traversing along the traverse groove (details will be described later in the embodiments). In this case, ribbon winding in which the yarn is continuously wound at substantially the same position in the axial direction of the winding bobbin is generated. In the present invention, the yarn end of the broken yarn is prevented from being wound into the winding drum, and therefore, the occurrence of ribbon winding can be effectively prevented.

The yarn winding machine according to claim 3 is characterized in that, in the yarn winding machine according to claim 1 or 2, the reference peripheral speed is 800m/min or less.

In the present invention, the switching mechanism is controlled at a timing when the peripheral speed of the winding drum is reduced to 800m/min or less. Accordingly, when the package having stopped rotating is brought into contact with the winding drum before stopping rotating again, damage to the package due to scraping with the winding drum can be effectively suppressed.

A fourth aspect of the present invention is a yarn winding method in a yarn winding machine including: a yarn feeding unit configured to feed yarn; a winding unit configured to perform a winding process of winding the yarn supplied from the yarn supplying unit on a winding bobbin to form a package; and a yarn joining mechanism for joining the yarn broken between the yarn feeding portion and the winding portion in a yarn traveling direction, wherein the winding portion includes: a cradle for rotatably supporting the package; a winding drum which rotates in contact with the package to thereby rotate the package; and a switching mechanism configured to switch a state of the winding unit between a contact state in which the package and the winding drum are in contact with each other and a separation state in which the package and the winding drum are separated from each other, wherein when the yarn is separated in the winding process, the package and the winding drum are separated by the switching mechanism before the yarn is spliced by the splicing mechanism, and further, rotation of the winding drum is stopped by controlling the drum driving unit and rotation of the package is stopped by controlling the braking unit, and when the package is stopped before the winding drum, the package and the winding drum are brought into contact with each other again by the switching mechanism at a timing at which a circumferential speed of the winding drum is equal to or lower than a predetermined reference circumferential speed before the winding drum is stopped from rotating.

In the present invention, as in the invention 1, it is possible to prevent the time from being prolonged from yarn breakage to yarn joining, and to prevent the broken yarn ends from being wound into the winding drum.

Drawings

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

Fig. 2 is a block diagram showing an electrical configuration of the automatic winder.

Fig. 3 is a front view of the winding unit.

Fig. 4 (a) is a side view of the upper side portion of the winding unit.

Fig. 4 (b) is a side view of the upper side portion of the winding unit.

Fig. 5 (a) is an explanatory diagram showing the operation of the upper yarn catching and guiding section.

Fig. 5 (b) is an explanatory diagram showing the operation of the upper yarn catching and guiding section.

Fig. 6 (a) is a reference diagram showing a state in which the yarn hangs down from the stopped package.

Fig. 6 (b) is a reference diagram showing a state in which the yarn hangs down from the stopped package.

Fig. 7 (a) is a reference diagram showing abnormal yarn paths.

Fig. 7 (b) is a reference diagram showing abnormal yarn paths.

Fig. 8 is a flowchart showing control from yarn disconnection to restarting of the winding process.

Fig. 9 is a graph showing a relationship between the circumferential speed of the winding drum and the timing, and a graph showing a relationship between the circumferential speed of the package and the timing.

Fig. 10 (a) is an explanatory diagram showing a state in which the yarn end hangs down from the package.

Fig. 10 (b) is an explanatory diagram showing a state in which the hanging yarn end is rewound into a package.

Detailed Description

Hereinafter, embodiments of the present invention will be described. The left-right direction of the paper surface in fig. 1 is set to be the left-right direction. The vertical direction of the paper surface in fig. 1 is defined as the vertical direction (vertical direction) in which gravity acts. The direction orthogonal to both the left-right direction and the up-down direction is referred to as the front-back direction. The yarn Y is set to travel in the yarn travel direction.

(outline constitution of automatic winder)

First, a schematic configuration of an automatic winder 1 (yarn winding machine of the present invention) according to the present embodiment will be described with reference to fig. 1 and 2. Fig. 1 is a front view of an automatic winder 1. Fig. 2 is a block diagram showing an electrical configuration of the automatic winder 1. The automatic winder 1 includes a plurality of winding units 2, doffing devices 3, and a machine body control device 4.

The plurality of winding units 2 are arranged in the left-right direction, and each wind the yarn Y drawn from the yarn supply bobbin Bs around the winding bobbin Bw to form the package P. The doffing device 3 is disposed above the plurality of winding units 2. The doffing device 3 is configured to be movable in the left-right direction. The doffing device 3 moves to the vicinity of the winding unit 2 when receiving a signal of full winding (formation of the package P is completed) from a certain winding unit 2, and performs removal of the package P from the winding unit 2, attachment of an empty winding bobbin Bw to the winding unit 2, and the like.

The body control device 4 is disposed laterally of the plurality of winding units 2 (see fig. 1). The machine body control device 4 is electrically connected to and communicates with a unit control portion 14 (see fig. 2, which will be described later) of the winding unit 2 and a control portion (not shown) of the doffing device 3.

Next, the structure of the winding unit 2 will be described mainly with reference to fig. 3 and fig. 4 (a) and (b). Fig. 3 is a schematic front view of the winding unit 2. Fig. 4 (a) and (b) are side views of the upper portion of the winding unit 2.

As shown in fig. 3, the winding unit 2 includes a yarn supplying section 11, a yarn processing executing section 12, and a winding section 13. The winding unit 2 is configured to wind the yarn Y by the winding unit 13 while performing a process by the yarn process executing unit 12 on the yarn Y supplied from the yarn supplying unit 11.

The yarn supply unit 11 supplies the yarn Y wound around the yarn supply bobbin Bs while unwinding the yarn Y. As shown in fig. 3, the yarn feeding portion 11 is disposed at the lowermost side of the winding unit 2. The yarn supplying portion 11 includes a yarn supplying bobbin supporting portion 21 and a yarn unwinding assisting device 22. The yarn supply bobbin supporting section 21 supports the yarn supply bobbin Bs in a substantially upright state. The yarn unwinding assisting device 22 restricts expansion of the yarn Y when it is unwound from the yarn supply bobbin Bs by the restricting tube 23. The regulating tube 23 is configured to move downward as the amount of yarn wound around the yarn supply bobbin Bs decreases, and to maintain the expansion at a constant level. Further, for example, a yarn contact 24 is disposed above the yarn unwinding assisting device 22. The yarn contact 24 is configured to detect the presence or absence of the advancing yarn Y.

The yarn processing executing section 12 is configured to execute various types of processing related to the yarn Y. As shown in fig. 3, the yarn processing executing section 12 is arranged between the yarn supplying section 11 and the winding section 13 in the up-down direction. The yarn processing executing section 12 includes a tension applying device 31, a yarn splicing mechanism 32, and a yarn clearer 33.

The tension applying device 31 applies a predetermined tension to the advancing yarn Y. The tension applying device 31 is disposed on the immediately upper side of the yarn feeding section 11. As an example of the tension applying device 31, a so-called shed-type device can be cited. As shown in fig. 3, a plurality of fixed canopy frame bodies 31a and a plurality of movable canopy frame bodies 31b are alternately arranged in the up-down direction. By adjusting the horizontal positions of the movable shed frames 31b, a predetermined tension is applied to the yarn Y running between the fixed shed frame 31a and the movable shed frame 31b.

The yarn joining mechanism 32 is a mechanism for joining the yarn Y (lower yarn Y1) on the yarn feeding portion 11 side and the yarn Y (upper yarn Y2) on the winding portion 13 side when the yarn Y is in a state of being disconnected (yarn Y disconnected) between the yarn feeding portion 11 and the winding portion 13 in the yarn advancing direction. Examples of the state where the yarn Y is broken include when the yarn cutter 33a cuts the yarn when a yarn defect is detected by the yarn clearer 33 described later, when the yarn is broken during winding of the package P, and when the yarn supply bobbin Bs is replaced. The yarn joining mechanism 32 includes a yarn joining device 34, a lower yarn catching guide 35, an upper yarn catching guide 36, and the like.

The yarn joining device 34 is a device for joining the lower yarn Y1 and the upper yarn Y2. The joining means 34 is, for example, a splicer in which the yarn ends are mated with each other by the action of compressed air. The yarn joining device 34 blows compressed air supplied from a compressed air source, not shown, to the lower yarn Y1 and the upper yarn Y2, temporarily loosens both ends, and then blows compressed air again to both ends to wind the ends around each other, thereby joining the ends. Alternatively, the joining device 34 may be a knotter that mechanically links the lower yarn Y1 and the upper yarn Y2.

The lower yarn catch guide 35 is configured to catch the lower yarn Y1 on the yarn supply bobbin Bs side (upstream side in the yarn traveling direction) and guide the lower yarn Y1 to the yarn splicing device 34. The lower yarn catching guide 35 is disposed below the yarn splicing device 34. The lower yarn catching and guiding portion 35 includes: a tubular arm 35b rotatable about the shaft 35 a; a suction portion 35c disposed at the distal end portion of the arm 35b for sucking and catching the yarn end portion of the lower yarn Y1; and a motor 37 for driving the arm 35b to rotate up and down. The lower yarn catch guide 35 is connected to a suction source, not shown. The upper yarn catching and guiding portion 36 is configured to catch the upper yarn Y2 on the package P side (downstream side in the yarn traveling direction) and guide the upper yarn Y2 to the yarn splicing device 34. The upper yarn catching and guiding portion 36 is disposed above the yarn splicing device 34. The upper yarn catching and guiding part 36 includes: a tubular arm 36b rotatable about the shaft 36 a; a suction portion 36c disposed at the tip of the arm 36b for sucking and catching the yarn end of the upper yarn Y2; and a motor 38 for driving the arm 36b to rotate up and down. The upper yarn catching and guiding portion 36 is connected to a suction source, not shown. The operation of the lower yarn catching guide 35 and the upper yarn catching guide 36 at the time of joining will be described later.

The yarn clearer 33 acquires information on the thickness of the advancing yarn Y and the like, and detects a yarn defect based on the information. The yarn clearer 33 is disposed, for example, above the yarn splicing device 34. The yarn clearer 33 has a cutter 33a. When the yarn defect is detected by the yarn clearer 33, the cutter 33a immediately cuts the yarn Y, and the yarn clearer 33 outputs a detection signal to the unit control portion 14.

The winding unit 13 performs a winding process of winding the yarn Y around the winding bobbin Bw to form the package P. As shown in fig. 3, the winding portion 13 is disposed at the uppermost side of the winding unit 2. The winding unit 13 includes a cradle 41, a winding drum 42, and a drum drive motor 43 (drum drive unit of the present invention). The winding unit 13 rotationally drives a winding drum 42 in contact with the package P rotatably supported by the cradle 41 by a drum drive motor 43, thereby rotating the package P to wind the yarn Y on the winding bobbin Bw.

The cradle 41 rotatably supports a winding bobbin Bw (package P). The cradle 41 supports the winding bobbin Bw at both ends by, for example, a cradle arm 41a disposed on the right side of the winding bobbin Bw and a cradle arm 41b disposed on the left side of the winding bobbin Bw. The rocker arms 41a and 41b are rotatably supported by a rotation shaft 41 c. Thereby, the cradle 41 can change the distance between the axial center of the winding bobbin Bw and the axial center of the winding drum 42 according to the diameter change of the package P. The cradle 41 can also be moved (rotated) by a moving mechanism 45 described later.

The cradle 41 is provided with a braking portion 44 for braking the rotation of the package P (decelerating the package P). The brake unit 44 includes, for example: a well-known cylinder 51 attached to the cradle arm 41 a; and a brake shoe 52 attached to the cylinder 51 and movable in the axial direction of the winding bobbin Bw. The brake unit 44 presses the brake shoe 52 against the winding bobbin Bw by the pressure of the compressed air supplied to the cylinder 51, thereby braking the rotation of the winding bobbin Bw (package P). The pressure of the compressed air is controlled by a known 1 st electromagnetic valve 53 (see fig. 2), for example. The 1 st solenoid valve 53 is electrically connected to the unit control section 14, and adjusts the supply and discharge of the compressed air in accordance with a command signal sent from the unit control section 14. The brake shoe 52 is movable between a position separated from the winding bobbin Bw and a position pressed against the winding bobbin Bw. For example, the brake shoe 52 is separated from the winding bobbin Bw when the pressure of the compressed air supplied to the cylinder 51 is low, and is pressed against the winding bobbin Bw when the pressure of the compressed air supplied to the cylinder 51 is high. When the brake shoe 52 is pressed against the winding bobbin Bw, the rotating package P is decelerated by friction with the brake shoe 52 (rotation of the package P is braked).

As shown in fig. 3, the winding unit 13 is provided with a moving mechanism 45 (switching mechanism of the present invention) for moving the cradle 41. The moving mechanism 45 includes, for example: a well-known cylinder 54; and a lifting member 55 attached to the cylinder 54 and movable in the up-down direction. The moving mechanism 45 moves the raising member 55 by supplying or discharging compressed air to or from the cylinder 54, and moves the cradle 41 between a contact position and a separation position, which will be described later.

The cylinder 54 is connected to a compressed air source, not shown, and moves the lifting member 55 upward when compressed air is supplied thereto, and moves the lifting member 55 downward when compressed air is discharged therefrom. The supply and discharge of the compressed air to and from the cylinder 54 are controlled by, for example, a 2 nd electromagnetic valve 56 (see fig. 2), which is a well-known three-way electromagnetic valve. The 2 nd solenoid valve 56 is electrically connected to the unit control portion 14, and switches the supply or discharge of the compressed air according to a command signal sent from the unit control portion 14.

The lifting member 55 is connected to the cylinder 54, and is in contact with the rocker arm 41a from below or attached to the rocker arm 41a, for example. The lifting member 55 does not lift the rocker arm 41a when compressed air is not supplied to the cylinder 54. At this time, the cradle 41 is positioned at a contact position where the outer peripheral surface of the package P and the outer peripheral surface of the winding drum 42 contact each other (see fig. 4 (a)). When compressed air is supplied to the cylinder 54, the lifting member 55 moves upward to lift the rocker arm 41a and separate the package P from the winding drum 42. At this time, the cradle 41 moves to a separation position (see a solid line in fig. 4 b) where the package P is separated from the winding drum 42. In this way, the moving mechanism 45 moves the cradle 41 between the contact position and the separation position. In other words, the moving mechanism 45 can switch the state of the winding portion 13 between a contact state in which the outer peripheral surface of the package P and the outer peripheral surface of the winding drum 42 are in contact with each other and a separation state in which the package P and the winding drum 42 are separated from each other. Hereinafter, the operation of separating the package P from the winding drum 42 will be referred to as lifting, and the operation of bringing the package P into contact with the winding drum 42 will be referred to as lowering.

A known rotation speed sensor 57 that can detect the rotation speed of the package P is provided near the cradle 41, for example, magnetically. The rotation speed sensor 57 is electrically connected to the unit control section 14 (see fig. 2), and transmits information on the rotation speed of the package P to the unit control section 14.

The winding drum 42 is a cylindrical member having an axial direction substantially parallel to the left-right direction. The diameter of the take-up drum 42 is, for example, 30cm. A traverse groove 42a for laterally moving (traversing) the yarn Y is formed in the outer peripheral surface of the winding drum 42. The winding drum 42 rotates the yarn Y while passing the yarn Y through the traverse groove 42a, thereby traversing the yarn Y by a predetermined width. Then, the winding drum 42 rotates while traversing the yarn Y through the traverse groove 42a in a state of being in contact with the outer peripheral surface of the package P, whereby the package P is driven to rotate by contact friction with the winding drum 42 (see fig. 4 (a)). Thereby, the yarn Y is wound around the winding bobbin Bw while traversing, and the package P is formed.

The drum drive motor 43 is a motor for rotationally driving the winding drum 42. The drum drive motor 43 is configured to be capable of rotationally driving the winding drum 42 in both a forward direction in which the yarn Y is wound around the package P and a reverse direction in which the yarn Y is pulled out from the package P. In the normal winding process, the winding drum 42 is driven to rotate in the normal direction to rotate the package P in the normal direction, and the yarn Y is wound around the winding bobbin Bw. In the case of a joint described later, the winding drum 42 is driven in reverse.

The drum drive motor 43 is provided with a known rotation speed sensor 58 (see fig. 2) that detects the rotation speed of the winding drum 42, for example, magnetically. The rotation speed sensor 58 is electrically connected to the unit control section 14 (see fig. 2), and transmits information on the rotation speed of the winding drum 42 to the unit control section 14.

The winding unit 2 further includes a unit control unit 14 (control unit of the present invention) (see fig. 2). The unit control section 14 includes CPU, ROM, RAM (storage section 14 a) and the like. The unit control unit 14 controls the respective units by the CPU in accordance with a program stored in the ROM. Specifically, the unit control unit 14 receives signals from the yarn clearer 33, the rotation speed sensors 57 and 58, and controls the joint device 34, the motor 37, the motor 38, the drum drive motor 43, the 1 st electromagnetic valve 53, the 2 nd electromagnetic valve 56, and the like. The unit control unit 14 outputs a signal requesting doffing to the doffing device 3 via the body control device 4.

In the winding unit 2 having the above configuration, the winding process for forming the package P is performed as follows. That is, the unit control section 14 drives the drum drive motor 43 to rotate the winding drum 42 in a state where the package P is brought into contact with the winding drum 42, whereby the package P is driven to rotate by friction with the winding drum 42. Thereby, the yarn Y pulled out from the yarn supply bobbin Bs is wound around the winding bobbin Bw to form the package P.

(operation of winding Unit at the time of Joint)

Next, the operation of the winding unit 2 at the time of the splicing will be described with reference to fig. 4 (a) and (b) and fig. 5 (a) and (b). Fig. 5 (a) and (b) are explanatory views showing the operation of the upper yarn catching and guiding section 36.

For example, at the time of winding process (see fig. 4 (a)), when the yarn defect is detected by the yarn clearer 33 and the yarn Y is cut by the cutter 33a, the unit control unit 14 controls each component of the winding unit 2, and performs the yarn splicing after temporarily stopping the winding process. Specifically, when the yarn Y is cut by the cutter 33a, the unit control portion 14 controls the 2 nd solenoid valve 56 (see fig. 2) to operate the moving mechanism 45 (see fig. 3) and moves the cradle 41 from the contact position (see fig. 4 a) to the separation position (see the solid line in fig. 4 b). Thereby, the package P is temporarily separated (lifted) from the winding drum 42. At this time, the upper yarn Y2 is wound around the package P rotated by inertia. Next, the unit control section 14 stops the rotation of the package P by controlling the 1 st electromagnetic valve 53 to actuate the braking section 44, and stops the rotation of the winding drum 42 by stopping the actuation of the drum drive motor 43.

Further, the unit control portion 14 controls the motor 38 (see fig. 2) in a state where the package P is brought into contact with the winding drum 42 again, and rotates the arm 36b of the upper yarn catching guide portion 36 upward so that the suction portion 36c is located in the vicinity of the package P (see fig. 5 a). Then, the unit control section 14 controls the motor 38 (see fig. 2) to rotate the arm 36b downward while reversing the drum drive motor 43. As a result, the upper yarn Y2 is pulled out from the package P in a state of being sucked and caught by the suction portion 36c, and is guided to the yarn splicing device 34 (see fig. 5 (b)). The unit control unit 14 controls the motor 37 (see fig. 2) to turn the arm 35b of the lower yarn catching and guiding unit 35 upward in a state where the suction unit 35c of the lower yarn catching and guiding unit 35 sucks the yarn end portion of the lower yarn Y1, and guides the lower yarn Y1 to the yarn splicing device 34 (not shown). Then, the unit controller 14 controls the yarn joining device 34 to join the guided lower yarn Y1 and the guided upper yarn Y2. After the completion of the joining, the unit control section 14 controls the respective components of the winding unit 2 to restart the winding process.

Here, conventionally, in order to prevent damage to the surface of the package P due to scraping from the winding drum 42, the rotation of the package P and the rotation of the winding drum 42 are completely stopped at the timing when the temporarily separated package P comes into contact with the winding drum 42 again. However, this method has the following problems. That is, when the package P stops rotating before the winding drum 42, the yarn end of the upper yarn Y2 may hang down from the package P after the rotation is stopped (see fig. 6 (a)), and may be wound into the winding drum 42 before the rotation is stopped. As a result, the yarn Y may be wound into a space (a space behind the winding drum 42) opposite to a traveling space (a space on the front side of the winding drum 42) of the yarn Y during normal winding process through the winding drum 42 (see fig. 6 b). In addition, when the package P is still lighter in the winding process (when the amount of the yarn Y wound around the winding bobbin Bw is small), the package P may stop rotating before the winding drum 42. At such timing, since the inertial mass of the rotating package P is small, the package P is easily decelerated by the braking portion 44.

When the yarn splicing is performed in this state (see fig. 7 (a) and (b)), the winding process is restarted in a state in which an abnormal yarn path is formed, and thus the package P is formed in a defective shape due to a failure to perform a traverse normally or the like. In this case, in particular, in the structure in which the yarn Y is traversed by the traverse groove 42a (see fig. 3) as in the present embodiment, the yarn Y is wound up without passing through the traverse groove 42a (i.e., without being traversed at all). Therefore, ribbon winding is generated in which the yarn Y is wound around the substantially same position in the axial direction of the package P.

To avoid this problem, consider: after bringing the winding drum 42 after stopping the rotation into contact with the package P again, the winding drum 42 is further rotated forward to rotate the package P, whereby the hanging yarn end is wound around the package P again. However, this method has a problem that the time from the disconnection of the yarn Y to the joining becomes long, and the production efficiency is lowered. Accordingly, the unit control unit 14 of the winding unit 2 performs the following control, thereby performing the yarn winding method capable of preventing a long time from breaking the yarn Y to splicing, and suppressing the broken yarn end of the yarn Y from being wound into the winding drum 42.

(yarn winding method)

The yarn winding method (that is, the content of the control performed by the unit control unit 14, specifically, the steps from the time when the yarn Y is disconnected during the winding process to the time when the winding process is restarted) according to the present embodiment will be described with reference to the flowchart of fig. 8, fig. 9, and (a) and (b) of fig. 10. Two graphs are shown in fig. 9. The 1 st graph shown on the upper side of the paper surface of fig. 9 is a graph showing the relationship between the circumferential speed of the winding drum 42 and the time. The vertical axis represents the circumferential speed of the winding drum 42, and the horizontal axis represents time. The 2 nd graph shown on the lower side of the paper surface of fig. 9 is a graph showing the relationship between the circumferential speed of the package P and the time. The vertical axis represents the circumferential velocity of the package P, and the horizontal axis represents the time. The scales of the moments in the two graphs are equal.

As an initial state, a normal winding process is performed in the winding unit 2. In the winding process, the unit control section 14 controls the drum drive motor 43 to rotate the winding drum 42 at a predetermined rotational speed. Further, information on the diameter of the winding drum 42 is stored in the storage portion 14a of the unit control portion 14. The unit control section 14 can calculate the circumferential speed of the winding drum 42 based on the rotational speed information of the winding drum 42 and the information on the diameter of the winding drum 42. The circumferential speed of the winding drum 42 in the winding process varies depending on the winding conditions, but is 1600m/min, for example. In the winding process, the unit control section 14 can calculate the diameter of the package P based on the circumferential speed information of the winding drum 42 and the rotational speed information of the package P detected by the rotational speed sensor 57. The peripheral speed of the package P in the winding process is basically substantially equal to the peripheral speed of the winding drum 42.

When the advancing yarn Y is disconnected (S101), the unit control unit 14 controls the 2 nd solenoid valve 56 (see fig. 2) to operate the moving mechanism 45 (see fig. 3) and move the cradle 41 from the contact position to the separation position (lift-up, S102). Thereby, the package P and the winding drum 42 are separated from each other. Examples of the cause of the yarn Y being broken during traveling include yarn breakage due to the yarn defect detection by the yarn clearer 33, yarn breakage due to unintended application of excessive tension to the yarn Y, and the like.

Next, the unit control section 14 starts deceleration of the package P and deceleration of the winding drum 42 (S103). Specifically, the unit control portion 14 controls the 1 st electromagnetic valve 53 (see fig. 2) to actuate the braking portion 44 (see fig. 3), thereby decelerating the package P. That is, the rotation of the package P is positively braked by the brake 44. The unit control section 14 also stops the operation of the drum drive motor 43, thereby decelerating the winding drum 42. The timing of the start of deceleration of the package P may be substantially the same (see time t1 in fig. 9), but is not necessarily substantially the same.

Next, the unit control section 14 predicts and compares the time required for the package P from the start of deceleration to the stop with the time required for the winding drum 42 from the start of deceleration to the stop, and determines whether the package P is stopped first or the winding drum 42 is stopped first (S104). The required time from the start of deceleration to the stop of the package P can be calculated (estimated) using, for example, information on the diameter of the package P immediately before the yarn Y being run is broken. That is, when the diameter of the package P is small and the inertial mass of the package P is small, the package P stops relatively quickly (see a solid line in a graph on the lower side of the paper of fig. 9 and a time t 2). In contrast, when the diameter of the package P is large and the inertial mass of the package P is large, it takes time until the package P stops (see a dot-dash line in a graph on the lower side of the paper of fig. 9 and time t 5). The required time from the start of deceleration to the stop of the winding drum 42 can be calculated using, for example, information on the peripheral speed of the winding drum 42 at the time of the winding process and information on the deceleration of the winding drum 42 at the time of stopping the operation of the drum drive motor 43. In the storage unit 14a, for example, information on the circumferential speed of the winding drum 42 and information on the deceleration of the winding drum 42 are stored in association with each other. Based on the stored information, it can be calculated (inferred) how many seconds have elapsed from the start of deceleration of the winding drum 42 and then stopped (see time t4 in fig. 9).

When it is determined that the package P is stopped before the winding drum 42 (yes in S104), the unit control unit 14 controls the 2 nd electromagnetic valve 56 to be lowered (S106) at a timing when the peripheral speed of the winding drum 42 is equal to or lower than the predetermined reference peripheral speed (yes in S105). The reference peripheral speed is a set value stored in the storage portion 14a, and is a peripheral speed at which damage to the surface of the package P becomes sufficiently small (i.e., adverse effect on the yarn quality becomes sufficiently small) when the package P comes into contact with the take-up drum 42 again. Specifically, the reference circumferential speed is, for example, 800m/min. In the present embodiment (that is, in the case where the diameter of the winding drum 42 is 30 cm), the reference circumferential speed is about 2680rpm when converted into the rotational speed. The timing at which the peripheral speed of the winding drum 42 becomes equal to or lower than the reference peripheral speed can be predicted based on the information or the like related to the deceleration and the set value of the reference peripheral speed (refer to time t3 in fig. 9).

In this way, when it is determined that the package P stops rotating before the winding drum 42, the unit control unit 14 controls the moving mechanism 45 so that the package P comes into contact with the winding drum 42 again before the winding drum 42 stops rotating. Thus, even when the upper yarn Y2 hangs down from the package P whose rotation was stopped (see fig. 10 a), the package P is brought into contact with the winding drum 42 before the rotation is stopped again, whereby the package P is driven to rotate again by friction with the winding drum 42. As a result, the upper yarn Y2 is wound again around the package P (see fig. 10 (b)).

On the other hand, when it is determined that the package P is simultaneously with the winding drum 42 or the rotation of the winding drum 42 is stopped after the winding drum 42 (S104: no), the unit control unit 14 controls the 2 nd solenoid valve 56 to descend (S107) immediately after the rotation of the package P is stopped. In this case, the winding drum 42 has stopped rotating when the package P stops rotating, and therefore, even if the upper yarn Y2 hangs down from the package P, the upper yarn Y2 cannot be wound into the winding drum 42.

Then, the unit control section 14 controls the joint mechanism 32 and the like to perform the above-described joint in a state where the package P descends and the package P and the winding drum 42 stop rotating (S108). After the completion of the joining, the unit control section 14 controls the winding section 13 and the like to restart the winding process (S109). In this way, control is performed from when the yarn Y is disconnected during the winding process to when the winding process is restarted.

As described above, the package P whose rotation has been stopped comes into contact with the winding drum 42 before the rotation has been stopped again at the timing when the circumferential speed of the winding drum 42 becomes equal to or lower than the reference circumferential speed. This can prevent the surface of the package P from being damaged by scraping against the winding drum 42, and can rotate the package P again by the force before the winding drum 42 stops rotating. Therefore, even when the yarn end temporarily hangs down from the package P, the yarn Y can be rewound into the package P, and the winding drum 42 can be stopped directly. Thus, the broken yarn end of the yarn Y can be prevented from being wound into the winding drum 42. In this way, the package P is brought into contact with the winding drum 42 before the rotation is stopped, and therefore, the winding drum 42 does not need to be additionally rotated after the rotation of the winding drum 42 is stopped, and the splicing can be started promptly. Thus, the time required for the splicing operation can be reduced as compared with the case where the winding drum 42 is additionally rotated. As described above, the yarn end of the broken yarn Y can be prevented from being wound into the winding drum 42 while the time from the breaking of the yarn Y to the joining can be prevented from being prolonged.

In the structure of traversing the yarn Y along the traverse groove 42a, when an abnormal yarn path is formed after the yarn is spliced by the yarn end hanging from the package P being wound into the winding drum 42, the yarn Y is not wound around the package P in a traversing manner along the traverse groove 42a. In this case, ribbon winding is generated in which the yarn is continuously wound around the bobbin at substantially the same position in the axial direction. In the present embodiment, the yarn end of the broken yarn Y is prevented from being wound into the winding drum 42, and therefore, the occurrence of ribbon winding can be effectively prevented.

The movement mechanism 45 is controlled at a timing when the circumferential speed of the winding drum 42 becomes lower than or equal to 800m/min. Accordingly, when the package P whose rotation is stopped is brought into contact with the winding drum 42 before the rotation is stopped again, damage to the package P due to contact (scraping) with the winding drum 42 can be effectively suppressed.

Next, a modified example in which the above embodiment is modified will be described. The same reference numerals are given to the same components as those of the above embodiment, and the description thereof will be omitted as appropriate.

(1) In the above embodiment, the yarn Y is traversed along the traverse groove 42a formed in the winding drum 42, but the present invention is not limited thereto. That is, the winding drum 42 may be provided with a traverse device for traversing the yarn Y separately from the winding drum 42 without providing a traverse groove. That is, the winding drum 42 may be configured to rotate only the package P.

(2) In the above embodiment, the reference peripheral speed of the winding drum 42 was 800m/min, but the present invention is not limited thereto. The reference peripheral speed of the take-up drum 42 may also be slower than 800m/min. Alternatively, the reference peripheral speed of the winding drum 42 may be faster than 800m/min as long as the package P, which is in contact with the winding drum 42 again before stopping the rotation, is not substantially damaged.

(3) In the above-described embodiment, the unit control portion 14 predicts and determines which of the package P and the winding drum 42 stops rotating first, but the present invention is not limited thereto. The unit control unit 14 may constantly monitor the rotational speed of the package P and the rotational speed of the winding drum 42, for example. The unit control unit 14 may determine that the package P is stopped when the rotational speed of the package P is first zero.

(4) In the above-described embodiment, the unit control section 14 predicts the timing at which the peripheral speed of the winding drum 42 becomes equal to or lower than the reference peripheral speed, but is not limited to this. For example, the rotation speed of the winding drum 42 may be constantly monitored, and the 2 nd electromagnetic valve 56 may be controlled to be lowered at a timing when the circumferential speed of the winding drum 42 becomes equal to or lower than the reference circumferential speed.

(5) In the above-described embodiment, the state of the winding portion 13 is switched between the contact state and the separation state by moving the cradle 41 by the moving mechanism 45, but the present invention is not limited thereto. That is, a not-shown moving mechanism for moving the winding drum 42 may be provided in addition to the moving mechanism 45 or instead of the moving mechanism 45.

(6) In the above-described embodiments, the unit control section 14 corresponds to the control section of the present invention, but is not limited thereto. For example, the body control unit 4 may control a plurality of winding units 2. In this case, the body control unit 4 corresponds to the control unit of the present invention.

(7) The present invention is not limited to the automatic winder 1, and can be applied to various yarn winding machines such as a spinning machine described in japanese patent application laid-open No. 2019-31380, for example.

(8) The 1 st electromagnetic valve 53 and the 2 nd electromagnetic valve 56 may be provided as a common electromagnetic valve. In this case, the timing at which the brake unit 44 is operated or stopped by the pressure of the compressed air supplied to the cylinder 51 and the timing at which the moving mechanism 45 moves the cradle 41 between the contact position and the separation position by supplying or discharging the compressed air to or from the cylinder 54 are synchronized, but this is not a problem in the aspect of the present invention. That is, when the switching mechanism is controlled so that the package P comes into contact with the winding drum again before the winding drum 42 stops rotating, the winding drum 42 is sufficiently decelerated. Therefore, even if the operation of the braking portion 44 is stopped while descending, and the rotation of the package P is free, the braking action can be generated on the package P by the frictional resistance with the winding drum 42. Therefore, the brake unit 44 and the moving mechanism 45 may be operated at substantially the same timing by using the common electromagnetic valve as described above.

Claims

1. A yarn winding machine is provided with: a yarn feeding unit configured to feed yarn; a winding unit configured to perform a winding process of winding the yarn drawn from the yarn supplying unit on a winding bobbin to form a package; and a yarn joining mechanism for joining the yarn broken between the yarn supplying portion and the winding portion in the yarn traveling direction, characterized in that,

the winding section includes:

a cradle rotatably supporting the package;

a winding drum which rotates by contacting the package, thereby rotating the package;

a drum driving unit for rotationally driving the winding drum;

a braking unit for braking the rotation of the package; and

a switching mechanism capable of switching the state of the winding portion between a contact state in which the package and the winding drum are in contact with each other and a separation state in which the package and the winding drum are separated from each other,

the yarn winding machine is provided with a control part,

the control part is provided with a control part,

in the winding process in which the winding drum rotates to rotate the package, the switching mechanism is controlled to separate the winding drum from the winding drum after the yarn is disconnected and before the yarn is spliced by the splicing mechanism, the drum driving unit is controlled to stop the winding drum from rotating and the braking unit is controlled to stop the winding drum from rotating,

the switching mechanism is controlled so that the package comes into contact with the winding drum again before the winding drum stops rotating.

2. A yarn winding machine as claimed in claim 1, characterized in that,

a traverse groove for traversing the yarn is formed in an outer peripheral surface of the winding drum, and when the package is stopped earlier than the winding drum, the switching mechanism is controlled so that the package comes into contact with the winding drum again before the winding drum stops rotating at a timing when a peripheral speed of the winding drum is equal to or lower than a predetermined reference peripheral speed.

3. A yarn winding machine as claimed in claim 2, characterized in that,

the reference peripheral speed is 800m/min or less.

4. A yarn winding method in a yarn winding machine, the yarn winding machine comprising: a yarn feeding unit configured to feed yarn; a winding unit configured to perform a winding process of winding the yarn supplied from the yarn supplying unit on a winding bobbin to form a package; and a yarn joining mechanism for joining the yarn broken between the yarn supplying portion and the winding portion in the yarn traveling direction, characterized in that,

the winding section includes:

a cradle for rotatably supporting the package;

a winding drum which rotates by contacting the package, thereby rotating the package; and

when the yarn is broken in the winding process, the package is separated from the winding drum by the switching mechanism and the winding drum is stopped from rotating and the package is stopped from rotating before the yarn is spliced by the splicing mechanism,

when the package is stopped before the winding drum, the package is brought into contact with the winding drum again by the switching mechanism before the winding drum stops rotating at a timing when the peripheral speed of the winding drum is equal to or lower than a predetermined reference peripheral speed.