Description:BACKGROUND OF THE INVENTION
[0001]
The present invention relates to a yarn winder.
[0002]
A winding unit (yarn winder) of Patent Literature 1 (Japanese Laid-Open Patent Publication No. 2021-11377) is configured to traverse and wind a yarn supplied from a yarn supply section while bringing a package into contact with a winding drum (contact roller) and rotating the winding drum so that the package is passively rotated. When the running yarn is disconnected for any reason, yarn ends of the disconnected yarn are joined (connected) by a yarn joining device. To be more specific, when the yarn is disconnected, (i) the package is distanced from the contact roller (i.e., the package is lifted up) and (ii) the package and the contact roller are decelerated. After that, the package is brought into contact with the contact roller (i.e., the package is taken down). A part of the disconnected yarn is provided on the package side, and basically has already been wound onto the package before rotation of the package stops. One yarn end of the disconnected yarn is provided on the package side while the other end thereof is provided on the yarn supply section side. These yarn ends thereof are sucked and captured by the respective sucking sections, and guided to the yarn joining device. Because of this, these two yarn ends are joined.

SUMMARY OF THE INVENTION
[0003]
The control of early starting the operation of a sucking section provided for sucking and capturing the yarn end of the disconnected yarn on the package side has been discussed in order to shorten the time required from the disconnection of the running yarn to the completion of yarn joining as much as possible. However, when this yarn end is sucked by this sucking section too early, the following problem may occur. That is, when the running yarn is disconnected, a part of a layer of a yarn (hereinafter, this will be referred to as the yarn layer) wound onto the package may be slackened on the surface of the package. Because of this, a gap is formed between the slackened yarn layer and the surface of the package. When sucking force is generated in the vicinity of the package by the sucking section before the package lifted up is taken down, the yarn end of the disconnected yarn on the package side or the slackened yarn layer may be moved so that this yarn end goes through the gap. When the package is taken down while this yarn end goes through the gap, this yarn end is sandwiched between the slackened yarn layer and a yarn layer provided inside the slackened yarn layer. When this yarn end or its surroundings (hereinafter, this will be referred to as the yarn end, etc.) is/are fixed onto the package to be immovable, the yarn end, etc. sucked and held by the sucking section may be dropped off from the sucking section while being guided to the yarn joining device. Assume that the yarn end, etc. has been guided to the yarn joining device. Even in this case, as the yarn joining is performed while the yarn end, etc. goes through the gap, a yarn layer in a defect state causing an unwinding defect in a later process is disadvantageously mixed in the package.
[0004]
An object of the present invention is (i) to restrain the time required from the disconnection of a yarn to the completion of yarn joining, from becoming long as much as possible and (ii) to restrain a yarn end of the disconnected yarn on the package side from going through a gap formed between a slackened yarn layer and the surface of the package.
[0005]
According to a first aspect of the invention, a yarn winder includes: a yarn supply section which is able to supply a yarn; a winding section configured to perform a winding operation of forming a package by winding the yarn supplied from the yarn supply section; a yarn connection mechanism configured to connect parts of the disconnected yarn in a case where the yarn is disconnected between the yarn supply section and the winding section; and a control unit. The winding section includes: a contact roller configured to rotate together with the package while being in contact with a surface of the package; and a lift mechanism which is able to perform (i) a distancing operation of distancing the surface of the package from an outer circumferential surface of the contact roller and (ii) a contact operation of bringing the surface of the package into contact with the outer circumferential surface of the contact roller. The yarn connection mechanism includes a sucking pulling mechanism which is able to perform a sucking pulling operation of sucking and capturing a yarn end of the disconnected yarn on the winding section side by means of a suction port and pulling the yarn end out from the package rotating in a reverse direction as compared to the winding operation. The control unit is able to perform: first control of causing the lift mechanism to perform the distancing operation in the case where the yarn is disconnected between the yarn supply section and the winding section; second control of causing the lift mechanism to perform the contact operation after the first control; and third control of causing the sucking pulling mechanism to perform a predetermined preparation so as to enable the sucking pulling operation. The sucking pulling mechanism is driven in the third control so that (i) the preparation is started before the completion of the contact operation performed in the second control and (ii) the preparation is completed after the completion of the contact operation.
[0006]
According to this aspect of the invention, the preparation performed by the sucking pulling mechanism is started before the completion of the contact operation. This suppresses an extremely late start of the sucking pulling operation. It is therefore possible to restrain the time required from the disconnection of the yarn to the completion of the yarn joining from becoming long, as much as possible. According to this aspect of the invention, the preparation is completed after the completion of the contact operation. This suppresses the movement of the yarn end before the completion of the contact operation. It is therefore possible to restrain the yarn end of the yarn on the package side from going through the gap formed between the slackened yarn layer and the surface of the package. With these arrangements, (i) the time required from the disconnection of the yarn to the completion of the yarn joining is restrained from becoming long as much as possible, and (ii) the yarn end of the yarn on the package side is restrained from going through the gap formed between the slackened yarn layer and the surface of the package.
[0007]
According to a second aspect of the invention, the yarn winder of the first aspect is arranged such that, when the running yarn is disconnected while the control unit controls the winding section to increase the circumferential speed of the package, the control unit performs the third control.
[0008]
When the circumferential speed of the package is increased, the circumferential speed of the package is lower than the target speed. When the yarn is disconnected while the circumferential speed of the package is still low, the package stops rotating in a shorter time than in the case where the yarn is disconnected while the circumferential speed of the package is sufficiently high (i.e., the circumferential speed thereof reaches the target speed). The following will describe a problem which may occur in this case. Typically, tension is applied to the running yarn wound by the winding section. When the running yarn is disconnected, this tension moves the yarn end of the yarn on the package side to leap toward the package side. As described above, when the running yarn is disconnected, a part of the yarn on the package side is wound onto the package until the rotation of the package stops. However, when the package stops rotating in a short time as described above, the circumferential speed of the package becomes considerably low before the yarn end of the yarn on the package side is wound. In this case, the yarn end is less likely to be wound onto the package. The above-described movement of the yarn end may not stop so that a part of the yarn is also slackened. This part of the yarn is close to the yarn end thereof, and has been already wound onto the package. As such, when the yarn is disconnected while the circumferential speed of the package is still low, the slackened yarn layer tends to be formed. As a result, the gap is easily formed between the slackened yarn layer and the surface of the package, and thus the yarn end of the yarn on the package side is highly likely to go through the gap. According to this aspect of the invention, the third control is performed in such a case so that the yarn end of the yarn on the package side is effectively restrained from going through the above-described gap. When the circumferential speed of the package is sufficiently high, all part of the yarn on the package side is sufficiently wound onto the package in a period between the disconnection of the yarn and the stop of rotation of the package. Therefore, the yarn which is disconnected and slackened is less likely to be wound onto the package. The control of causing the preparation to be completed before the completion of the contact operation may be performed instead of the third control in the case where the yarn is disconnected while the circumferential speed of the package is sufficiently high. This shortens the time required from the disconnection of the yarn and the completion of the yarn joining.
[0009]
According to a third aspect of the invention, the yarn winder of the first or second aspect is arranged such that the sucking pulling mechanism includes: a fluid path connecting the suction port to a sucking power source configured to generate negative pressure at the suction port; and a shutter section which is able to open and close the fluid path, and the preparation includes a first preparation in which the shutter section opens the fluid path. In this case, the control unit is configured to drive the shutter section so that, in the third control, the first preparation is completed after the completion of the contact operation.
[0010]
This suppresses the occurrence of high negative pressure at the suction port before the completion of the contact operation. It is therefore possible to effectively restrain the negative pressure from moving the yarn end before the completion of the contact operation.
[0011]
According to a fourth aspect of the invention, the yarn winder of any one of the first to third aspects is arranged such that the sucking pulling mechanism includes a movement mechanism configured to move the suction port between a predetermined standby position and a suction position which is closer to the package than the standby position is and which is provided for sucking the yarn end, the preparation includes a second preparation in which the movement mechanism moves the suction port from the standby position to the suction position, and the control unit is configured to drive the movement mechanism so that, in the third control, the second preparation is completed after the completion of the contact operation.
[0012]
This avoids the case where the suction port reaches the suction position before the completion of the contact operation. Therefore, even when the negative pressure is generated at the suction port, the negative pressure is effectively restrained from moving the yarn end before the completion of the contact operation.
[0013]
According to a fifth aspect of the invention, the yarn winder of the first or second aspect is arranged such that the sucking pulling mechanism includes: a movement mechanism configured to move the suction port between a predetermined standby position and a suction position which is closer to the package than the standby position is and which is provided for sucking the yarn end; a fluid path connecting the suction port to a sucking power source configured to generate negative pressure at the suction port; and an openable portion which is configured to close the fluid path in accordance with the movement mechanism in a case where the suction port is provided at the standby position, and to open the fluid path in accordance with the movement mechanism in a case where the suction port is provided at the suction position. In this case, the preparation includes a movement operation of moving the suction port from the standby position to the suction position, and the control unit is configured to drive the movement mechanism so that, in the third control, the movement operation is completed after the completion of the contact operation.
[0014]
This avoids the case where the suction port reaches the suction position before the completion of the contact operation, and suppresses the occurrence of the high negative pressure at the suction port before the completion thereof. It is therefore possible to effectively restrain the negative pressure from moving the yarn end before the completion of the contact operation.
[0015]
According to a sixth aspect of the invention, the yarn winder of any one of the first to fifth aspects is arranged such that the contact roller includes a traversing groove which is formed on the outer circumferential surface of the contact roller and which is provided for traversing the running yarn.
[0016]
Typically, the contact roller is configured to apply contact pressure to the surface of the package. This restrains the yarn wound onto the package from being slackened. According to this aspect of the invention, the yarn is traversed along the traversing groove. Unlike the case where the traversing groove is not formed on the outer circumferential surface of the contact roller, the yarn of this arrangement which is about to be wound onto the package does not make contact with the outer circumferential surface of the contact roller. That is, the contact pressure is applied only to the yarn which has been wound onto the package. Furthermore, when the running yarn is disconnected, the package is distanced from the contact roller by the first control. Therefore, when (i) the yarn has been disconnected and (ii) a part of the yarn is still not wound onto the package, this part of the yarn is not pressed onto the surface of the package. Therefore, this part of the yarn is highly likely to be included in the package while being distanced from the surface. As a result, the gap is highly likely to be formed in the above-described case. The third control is therefore especially effective.

BRIEF DESCRIPTION OF THE DRAWINGS
[0017]
FIG. 1 is a front elevation of an automatic winder of the present embodiment.
FIG. 2 is a block diagram of an electric configuration of the automatic winder.
FIG. 3 is a front elevation which schematically shows a yarn winding unit.
FIG. 4 is a side view which schematically shows a part of the yarn winding unit in an up-down direction.
FIGs. 5(a) and 5(b) show the operation of a winding section.
FIGs. 6(a) and 6(b) show the operation of a yarn processing execution section and that of the winding section.
FIGs. 7(a) to 7(c) are reference drawings which show a problem due to slackening of a yarn on the surface of a package.
FIG. 8 is a flowchart showing a flow from the disconnection of the running yarn to the restart of a winding operation.
FIG. 9 is a flowchart showing the details of a part of a process shown in the flowchart of FIG. 8.
FIG. 10 is a flowchart regarding a modification.
FIG. 11 is a flowchart regarding another modification.
FIGs. 12(a) and 12(b) show an upper yarn capturing guide section of another modification and its surroundings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018]
The following will describe an embodiment of the present invention. As shown in FIG. 1, a direction in which yarn winding units 2 described later are aligned will be referred to as a left-right direction for the sake of convenience. Furthermore, a direction in which the gravity works will be referred to as an up-down direction. Furthermore, a direction orthogonal to both the left-right direction and the up-down direction will be referred to as a front-rear direction.
[0019]
(Outline of Automatic Winder)
To begin with, the following will outline an automatic winder 1 of the present embodiment, with reference to FIG. 1 and FIG. 2. FIG. 1 is a front elevation of the automatic winder 1. FIG. 2 is a block diagram of an electric configuration of the automatic winder 1. As shown in FIG. 1 and FIG. 2, the automatic winder 1 includes the yarn winding units 2, a doffing device 3, and a machine controller 4. Each yarn winding unit 2 is equivalent to a yarn winder of the present invention.
[0020]
Each yarn winding unit 2 is configured to form a package P by winding a yarn Y pulled out from a yarn supplying bobbin Bs onto a winding bobbin Bw (see FIG. 3). As shown in FIG. 1, the yarn winding units 2 are aligned in the left-right direction.
[0021]
The doffing device 3 is configured to perform operations such as the detachment of a fully-wound package P from each yarn winding unit 2 and the attachment of an empty winding bobbin Bw to each yarn winding unit 2. As shown in FIG. 1, the doffing device 3 is provided above the yarn winding units 2. The doffing device 3 is movable in the left-right direction. When receiving a signal indicating that the package P is fully wound from one yarn winding unit 2, the doffing device 3 moves to a position above this yarn winding unit 2 and performs the above-described operations.
[0022]
As shown in FIG. 1, for example, the machine controller 4 is positioned to the left of the yarn winding units 2. The machine controller 4 is electrically connected to a unit controller 15 (see FIG. 2) of each yarn winding unit 2 and a controller (not illustrated) of the doffing device 3, and communicates with these controllers.
[0023]
(Yarn Winding Unit)
The following will describe the structure of each yarn winding unit 2 with reference to FIG. 2 to FIG. 4. FIG. 3 is a front elevation which schematically shows the yarn winding unit 2. FIG. 4 is a side view which schematically shows a part of the yarn winding unit 2 in the up-down direction.
[0024]
As shown in FIG. 3, the yarn winding unit 2 includes a frame 10, a yarn supplying section 11, a yarn processing execution section 12, a winding section 13, and the unit controller 15. The frame 10 is, e.g., a hollow member extending in the up-down direction. The installation location of the frame 10 is fixed. The yarn supply section 11, the yarn processing execution section 12, and the winding section 13 are provided on the frame 10, and aligned in this order from the upstream side in a yarn path in which the yarn Y runs. The unit controller 15 is, e.g., accommodated in the frame 10. The unit controller 15 is equivalent to a control unit of the present invention.
[0025]
The yarn supply section 11 is configured to supply the yarn Y wound onto the yarn supplying bobbin Bs as the yarn Y is unwound. The yarn supplying section 11 includes a yarn supplying bobbin supporter 21 and a yarn unwinding assisting device 22. The yarn supplying bobbin supporter 21 supports the yarn supplying bobbin Bs to be substantially in an upright state. The yarn unwinding assisting device 22 is configured to adjust, by means of an adjusting cylinder 23, a bulge which is formed when the yarn Y is unwound from the yarn supplying bobbin Bs. The adjusting cylinder 23 is configured to move downward as the amount of the yarn wound onto the yarn supplying bobbin Bs decreases, so as to keep the size of the above-described bulge to be constant.
[0026]
The yarn processing execution section 12 is configured to execute various processes regarding the yarn Y. The yarn processing execution section 12 includes a yarn feeler 31, a tensioner 32, a yarn joining device 33, and a yarn clearer 34.
[0027]
The yarn feeler 31 is able to detect the existence of the yarn Y between the yarn unwinding assisting device 22 and the tensioner 32. The tensioner 32 is able to apply a predetermined tension to the running yarn Y. The tensioner 32 is, e.g., a gate-type device. As shown in FIG. 3, fixed gate members 32a and movable gate members 32b are alternately arranged in the up-down direction. By adjusting the horizontal positions of the movable gate members 32b, a predetermined tension is applied to the yarn Y running between the fixed gate members 32a and the movable gate members 32b.
[0028]
When the yarn Y is disconnected between the yarn supply section 11 and the winding section 13, one part of the yarn Y is provided on the yarn supply section 11 side while the other part thereof is provided on the winding section 13 side. The yarn joining device 33 is configured to join these parts of the yarn Y together. Hereinafter, for the sake of convenience, one part of the disconnected yarn Y on the yarn supply section 11 side will be referred to as a lower yarn Y1. Furthermore, the other part of the disconnected yarn Y on the winding section 13 side (i.e., the other part of the yarn Y on the package P side) will be referred to as an upper yarn Y2. The yarn joining device 33 is, e.g., a compressed-air type device. The yarn joining device 33 blows compressed air, which is supplied from an unillustrated compressed air source, onto the lower yarn Y1 and the upper yarn Y2 so that both yarn ends of the yarn Y are temporarily disentangled. After that, the yarn joining device 33 blows the compressed air onto both yarn ends of the yarn Y again so that the yarn ends thereof are entangled and joined together.
[0029]
A lower yarn capturing guide section 35 configured to capture and guide the lower yarn Y1 toward the yarn joining device 33 is provided below the yarn joining device 33. The lower yarn capturing guide section 35 includes an axis 35a, an arm 35b, and a suction port 35c. The axis 35a extends, e.g., along the left-right direction. The arm 35b is a pipe-shaped member rotatable about the axis 35a. The suction port 35c is provided at a leading end portion of the arm 35b. The suction port 35c is able to suck and capture a yarn end of the lower yarn Y1. The arm 35b is rotated by an arm motor 37.
[0030]
An upper yarn capturing guide section 36 configured to capture and guide the upper yarn Y2 toward the yarn joining device 33 is provided above (downstream of) the yarn joining device 33. The upper yarn capturing guide section 36 includes an axis 36a, an arm 36b, and a suction port 36c. The axis 36a extends, e.g., along the left-right direction. The arm 36b is a pipe-shaped member rotatable about the axis 36a. The suction port 36c is provided at a leading end portion of the arm 36b. The suction port 36c is able to suck and capture a yarn end of the upper yarn Y2. The arm 36b is rotated by an arm motor 38. The arm motor 38 is equivalent to a movement mechanism of the present invention. In the present embodiment, the arm motor 38 is included in the upper yarn capturing guide section 36.
[0031]
As shown in FIG. 4, the upper yarn capturing guide section 36 is connected to a negative pressure source 102 via a duct 101. For example, a fluid path 101a in which air flows is formed inside the duct 101. The fluid path 101a is provided for sucking the yarn Y from the suction port 36c toward the negative pressure source 102 side, along with the air. The negative pressure source 102 is, e.g., a known blower device. For example, the negative pressure source 102 may be shared by the yarn winding units 2. The negative pressure source 102 is equivalent to a sucking power source of the present invention. In this case, although not illustrated in the figures, a common duct shared by the yarn winding units 2 is provided between the duct 101 and the negative pressure source 102 in a flow direction of the air. By negative pressure generated at the suction port 36c, the air is sucked into the negative pressure source 102 through the arm 36b, the duct 101, and the common duct. As a result, the yarn Y is sucked into the suction port 36c along the air and captured by the upper yarn capturing guide section 36. The lower yarn capturing guide section 35 is also connected to the negative pressure source 102 via an unillustrated duct. The operations of the lower yarn capturing guide section 35 and upper yarn capturing guide section 36 in yarn joining will be described later.
[0032]
As shown in FIG. 4, a shutter section 39 which is able to open and close the fluid path 101a is provided at an intermediate part of the fluid path 101a. This intermediate part is provided between the suction port 36c and the negative pressure source 102 in a sucking direction in which the yarn Y is sucked. The shutter section 39 includes, e.g., a shutter 39a and a shutter motor 39b. The shutter 39a is able to switch its state between a closed state of closing the fluid path 101a and an open state of opening the fluid path 101a. As the shutter 39a is switched to the open state, a space around the suction port 36c communicates with the negative pressure source 102 so that the negative pressure is generated at the suction port 36c and its surroundings. The shutter 39a is moved by the shutter motor 39b. The shutter motor 39b is, e.g., a known stepping motor. The shutter motor 39b is electrically connected to, e.g., the unit controller 15. A combination of the upper yarn capturing guide section 36 and the shutter section 39 is equivalent to a sucking pulling mechanism of the present invention.

[0033]
The yarn clearer 34 is able to acquire information of the thickness of the running yarn Y. The yarn clearer 34 is configured to detect a yarn defect based on this information. A cutter 34a is provided in the vicinity of the yarn clearer 34. When the yarn clearer 34 detects a yarn defect, the cutter 34a immediately cuts the yarn Y. At substantially the same time, the yarn clearer 34 outputs a detection signal to the unit controller 15.
[0034]
The winding section 13 is able to perform the winding operation of forming the package P by winding the yarn Y onto the winding bobbins Bw. As shown in FIG. 3, the winding section 13 includes a cradle 41, a traversing drum 42, a drum driving motor 43, and a lift mechanism 44.
[0035]
The cradle 41 is configured to hold the winding bobbin Bw (i.e., package P) so that the winding bobbin Bw is freely rotatable. As shown in FIG. 3, the cradle 41 is configured to support both ends of the winding bobbin Bw by means of, e.g., cradle arms 41a and 41b. The cradle arm 41a is positioned to the right of the winding bobbin Bw. The cradle arm 41b is positioned to the left of the winding bobbin Bw. The positions of the cradle arms 41a and 41b may be reversed in the left-right direction. The cradle arms 41a and 41b are swingably supported by a swing shaft 41c. The cradle 41 is able to swing between a contact position (see FIG. 4; indicated by two-dot chain lines in FIG. 5(b)) and a distanced position (indicated by full lines in FIG. 5(b)) by means of the lift mechanism 44. The contact position is the position of the cradle 41 in the case where the package P is in contact with the traversing drum 42. When the cradle 41 is at the contact position, the surface Pa of the package P is pressed onto an outer circumferential surface 42b of the traversing drum 42. The distanced position is the position of the cradle 41 in the case where the package P is distanced from the traversing drum 42. The cradle 41 is provided with a brake section 45 configured to control the rotation of the package P. The brake section 45 is attached to, e.g., the cradle arm 41a. For example, an unillustrated rotation sensor configured to detect the rotation number of the package P may be provided at the cradle 41 or its surroundings.
[0036]
The traversing drum 42 is configured to cause the package P to passively rotate, and to traverse the running yarn Y. The traversing drum 42 is equivalent to a contact roller of the present invention. As shown in FIG. 3 and FIG. 4, the traversing drum 42 is substantially cylindrical in shape. The rotational axis direction of the traversing drum 42 is substantially in parallel to the left-right direction. A traversing groove 42a for traversing the yarn Y is formed on the outer circumferential surface 42b of the traversing drum 42. As the traversing drum 42 in contact with the surface Pa of the package P rotates, the package P is passively rotated by friction force. At this time, as the traversing drum 42 rotates while the yarn Y is threaded to the traversing groove 42a, the yarn Y is traversed in the left-right direction. As a result, the yarn Y is traversed and wound onto the winding bobbin Bw. The traversing drum 42 has a function of adjusting the shape of the package P. That is, as the surface Pa of the package P is pressed onto the outer circumferential surface 42b of the traversing drum 42, the outer circumferential surface 42b applies contact pressure to the surface Pa.
[0037]
The drum driving motor 43 is configured to rotate the traversing drum 42. The drum driving motor 43 is able to rotate the traversing drum 42 both in a positive direction and a reverse direction. The positive direction is a rotational direction of the traversing drum 42 in the case where the yarn Y is wound onto the winding bobbin Bw. The reverse direction is the rotational direction of the traversing drum 42 in the case where the upper yarn Y2 is pulled out from the package P at the time of the yarn joining. The drum driving motor 43 is electrically connected (see FIG. 2) to the unit controller 15. The drum driving motor 43 may include an unillustrated rotary encoder provided for detecting the rotation number of the traversing drum 42. Alternatively, an unillustrated rotation number sensor may be provided in the vicinity of the traversing drum 42.
[0038]
The lift mechanism 44 is able to move the package P up and down. As shown in FIG. 3, the lift mechanism 44 includes, e.g., an air cylinder 44a and a lifting member 44b. The air cylinder 44a includes, e.g., an unillustrated piston rod which is able to extend and contract by means of the compressed air. For example, the air cylinder 44a causes the piston rod (i) to extend as the compressed air is supplied and (ii) to contract as the compressed air is exhausted. The lifting member 44b is supported by, e.g., the piston rod. The lifting member 44b supports, e.g., the cradle arm 41a. The lifting member 44b is configured to cause the cradle 41 to swing (i.e., configured to move the package P up or down) as the piston rod extends or contracts. The supply and exhaust of the compressed air to and from the air cylinder 44a may be controlled by, e.g., an unillustrated electromagnetic valve. The electromagnetic valve is electrically connected to, e.g., the unit controller 15. That is, the lift mechanism 44 is electrically connected (see FIG. 2) to the unit controller 15.
[0039]
For example, when the compressed air is not supplied to the air cylinder 44a, the lift mechanism 44 puts the cradle 41 at a position to bring the surface Pa of the package P into contact with the outer circumferential surface 42b of the traversing drum 42. Furthermore, when the compressed air is supplied to the air cylinder 44a, the lift mechanism 44 moves the package P up. As a result, the surface Pa of the package P is distanced from the outer circumferential surface 42b of the traversing drum 42. Hereinafter, the operation of moving the package P up may be referred to as a distancing operation. For example, when the compressed air is exhausted from the air cylinder 44a, the lift mechanism 44 moves the package P down. As a result, the package P approaches the traversing drum 42 so that the surface Pa of the package P makes contact with the outer circumferential surface 42b of the traversing drum 42. Hereinafter, the operation of moving the package P down may be referred to as a contact operation. In the present embodiment, the contact operation is started as the above-described electromagnetic valve of the lift mechanism 44 is opened. The contact operation is completed as the surface Pa of the package P makes contact with the outer circumferential surface 42b of the traversing drum 42.
[0040]
The unit controller 15 includes, e.g., a CPU, a ROM, and a RAM which are unillustrated. The unit controller 15 is configured to control components by means of the CPU, based on a program stored in the ROM. To be more specific, the unit controller 15 is configured to control (see FIG. 2) the yarn joining device 33, the arm motor 37, the arm motor 38, the shutter motor 39b, the drum driving motor 43, the lift mechanism 44, etc. The unit controller 15 is also configured to receive (see FIG. 2) a signal from the yarn clearer 34, etc. The unit controller 15 is also configured to output a signal for requesting the doffing device 3 to perform doffing. This signal is sent to a controller (not illustrated) of the doffing device 3 via the machine controller 4.
[0041]
In the yarn winding unit 2 having the above-described structure, while bringing the package P into contact with the traversing drum 42, the unit controller 15 drives the drum driving motor 43 to rotate the traversing drum 42. As a result, the yarn Y pulled out from the yarn supplying bobbin Bs is wound onto the winding bobbin Bw so that the package P is formed (the winding operation).
[0042]
(Operation of Yarn Winding Unit in Yarn Joining)
The following will describe the operation of the yarn winding unit 2 in the yarn joining, with reference to FIG. 5(a) to FIG. 6(b). FIG. 5(a) shows a state of the winding section 13 during the winding operation. FIG. 5(b) shows a state of the winding section 13 after the running yarn Y is disconnected. FIG. 6(a) shows a state of the yarn processing execution section 12 and that of the winding section 13 after the completion of a preparation which is described later and which is performed by the yarn processing execution section 12. FIG. 6(b) shows a state of the yarn processing execution section 12 and that of the winding section 13 after the completion of the sucking pulling operation which is described later and which is performed by the yarn processing execution section 12.
[0043]
During the winding operation (see FIG. 5(a)), the running yarn Y may be disconnected. The reasons of disconnection of the yarn Y are described below. For example, when excessive tension is unintentionally applied to the yarn Y, yarn breakage occurs so that the yarn Y is disconnected. For example, when (i) the yarn clearer 34 detects a yarn defect and (ii) the cutter 34a cuts the yarn Y, the yarn Y is disconnected.

[0044]
When the yarn Y is disconnected, the winding section 13 stops the winding operation. To be more specific, the lift mechanism 44 moves the package P up (the distancing operation; see FIG. 5(b)). A main object of the distancing operation is to avoid, when the rotation of the package P is stopped, the damage of the surface Pa due to the friction with the traversing drum 42. After the package P is moved up, the drum driving motor 43 stops the rotation of the traversing drum 42. The brake section 45 stops the rotation of the package P. A part of the disconnected yarn Y on the package P side, i.e., the upper yarn Y2 is wound onto the package P until the rotation of the package P stops. As a result, the yarn end of the upper yarn Y2 is included in the package P whose rotation is stopped.
[0045]
For example, the yarn processing execution section 12 and the winding section 13 perform the yarn joining after the rotation of the traversing drum 42 and that of the package P are stopped. In the yarn joining, the lift mechanism 44 moves the package P down at an appropriate timing. The details will be given later.
[0046]
In the yarn joining, the upper yarn capturing guide section 36 and shutter section 39 of the yarn processing execution section 12 perform the preparation as below. The preparation is performed before the sucking pulling operation described later, and is a predetermined operation for allowing the sucking pulling operation to be started.
[0047]
Before the preparation, the arm 36b is provided at a predetermined standby position (see FIG. 5(b)). Furthermore, the shutter 39a of the shutter section 39 (see FIG. 4) is at the closed state. In the preparation, the shutter section 39 switches the state of the shutter 39a from the closed state to the open state. This opens the fluid path 101a having been closed, and the negative pressure which can suck and capture the yarn end of the upper yarn Y2 is generated inside the suction port 36c. The operation of switching the state of the shutter section 39 from the state of closing the fluid path 101a to the state of opening the fluid path 101a is equivalent to a first preparation of the present invention. The first preparation is included in the preparation. In the preparation, the arm 36b is rotated upward from the standby position by the arm motor 38. Because of this, the suction port 36c moves close to a suction position (indicated by full lines in FIG. 6(a)) which is closer to the package P than the standby position (indicated by two-dot chain lines in FIG. 6(a)). The suction position is a position in the vicinity of the package P, and provided for sucking the yarn end of the upper yarn Y2. Such operation of the upper yarn capturing guide section 36 is equivalent to a second preparation of the present invention. The second preparation is included in the preparation.
[0048]
After the completion of the preparation, the upper yarn capturing guide section 36 performs the sucking pulling operation as below. The upper yarn capturing guide section 36 pulls the yarn end of the upper yarn Y2 out from the package P rotating in a reverse direction as compared to the winding operation, in cooperation with the winding section 13. To be more specific, the drum driving motor 43 rotates the traversing drum 42 in a reverse direction as compared to the winding operation. Because of this, the package P rotates in a reverse direction as compared to the winding operation. At substantially the same time as such reverse rotation of the package P, the suction port 36c starts sucking the yarn end of the upper yarn Y2 and captures this yarn end (i.e., sucks and captures this yarn end). After sucking and capturing the upper yarn Y2, the arm 36b is rotated downward by the arm motor 38. As a result, the upper yarn Y2 is guided to the yarn joining device 33 by the upper yarn capturing guide section 36 as shown in FIG. 6(b). The above-described operation of the upper yarn capturing guide section 36 is the sucking pulling operation.
[0049]
Although not illustrated in the figures, the lower yarn capturing guide section 35 sucks and captures the yarn end of the lower yarn Y1 by means of the suction port 35c at substantially the same time as the upper yarn capturing guide section 36 performs the sucking pulling operation. Furthermore, the arm 35 is rotated upward by the arm motor 37. Because of this, the lower yarn capturing guide section 35 guides the lower yarn Y1 to the yarn joining device 33. The yarn joining device 33 joins (connects) the lower yarn Y1 guided by the lower yarn capturing guide section 35 and the upper yarn Y2 guided by the upper yarn capturing guide section 36 together. As a result, the yarn joining is completed, and the winding operation can be restarted.
[0050]
As described above, the yarn joining is performed by the yarn processing execution section 12 and the winding section 13 in cooperation with each other. A combination of the yarn processing execution section 12 and the winding section 13 is equivalent to a yarn connection mechanism of the present invention.
[0051]
(Timing of Sucking and Capturing Yarn End)
The control of starting the operation of the upper yarn capturing guide section 36 early has been discussed in order to shorten the time required from the disconnection of the running yarn Y to the completion of the yarn joining as much as possible. However, when the suction of this yarn end is started too early, the following problem may occur. The following describes this problem with reference to FIG. 7(a) to FIG. 7(c). FIGs. 7(a) to 7(c) are reference drawings showing a problem due to slackening of the upper yarn Y2 on the surface Pa of the package P. FIG. 7(a) and FIG. 7(b) are side views showing a part of the yarn winding unit 2 in the up-down direction. Similarly, FIG. 7(c) is a plan view which schematically shows the yarn winding unit 2.
[0052]
As described above, when the yarn Y is disconnected during the winding operation, the lift mechanism 44 moves the package P up. Furthermore, the rotation of the package P is stopped. As a result of the disconnection, the upper yarn Y2 is wound onto the package P until the rotation of the package P stops. When a layer of the yarn Y (i.e., the yarn layer) is formed on the surface Pa of the package P after the package P is moved up, the surface Pa of the package P is distanced from the outer circumferential surface 42b of the traversing drum 42. With this arrangement, the upper yarn Y2 is wound while the contact pressure is not applied to the surface Pa. Because of this, as shown in FIG. 7(a), a part of the yarn layer may be slackened on the surface Pa of the package P. In this case, a gap G is formed between the slackened yarn layer and the surface Pa of the package P. It should be noted that the gap G is relatively exaggerated for easy understanding of the figures.
[0053]
A yarn end Ye (see FIG. 7(a) to FIG. 7(c)) of the upper yarn Y2 may be sucked toward the suction port 36c before the completion of the contact operation. In this case, the yarn end Ye may go through the gap G as shown in FIG. 7(b) and FIG. 7(c). When the contact operation is performed while the yarn end Ye goes through the gap G, the yarn end Ye is sandwiched between the slackened yarn layer and a yarn layer provided inside the slackened yarn layer. When this yarn end Ye or its surroundings (hereinafter, this will be referred to as the yarn end Ye, etc.) is/are fixed onto the package P to be immovable, the yarn end Ye, etc. may drop off from the sucking port 36c while being guided to the yarn joining device 33. In this case, a defect in which the yarn joining cannot be performed occurs. Assume that the yarn end Ye, etc. has been guided to the yarn joining device 33. Even in this case, as the yarn joining is performed while the yarn end Ye, etc. goes through the gap G, a yarn layer in a defect state causing an unwinding defect in a later process is disadvantageously mixed in the package P.
[0054]
Therefore, the following control is performed in the yarn winding unit 2 for restraining (i) the time, which is required from the disconnection of the yarn Y to the completion of the yarn joining, from becoming long as much as possible and (ii) the yarn end Ye from going through the gap G formed between the slackened yarn layer and the surface Pa of the package P.
[0055]
(Control From Stop to Restart of Winding Operation)
The following will describe the control performed by the unit controller 15 from the stop to restart of the winding operation, mainly with reference to flowcharts of FIG. 8 and FIG. 9. FIG. 8 is a flowchart showing a flow from the disconnection of the running yarn Y to the restart of the winding operation. FIG. 9 is a flowchart showing the details of a part of a process (specifically, a later-described step S102) shown in the flowchart of FIG. 8.
[0056]
In an initial state, the winding operation is performed in the yarn winding unit 2. During the winding operation, the yarn Y is disconnected for any reason (step S101 in FIG. 8). The disconnection of the yarn Y is detected by, e.g., the yarn clearer 34. The yarn clearer 34 outputs a detection signal indicating the disconnection of the yarn Y.
[0057]
Upon receiving the detection signal, the unit controller 15 controls the winding section 13 to stop the winding operation (step S102). To be more specific, the unit controller 15 causes the lift mechanism 44 to move the package P up (the distancing operation) in the step S102. The control of the unit controller 15 to cause the lift mechanism 44 to perform the distancing operation is equivalent to first control of the present invention. The unit controller 15 also controls the drum driving motor 43 to stop the rotation of the traversing drum 42 in the step S102. The unit controller 15 also controls the brake section 45 to stop the rotation of the package P in the step S102. The unit controller 15 also causes (i) the sucking pulling mechanism (the upper yarn capturing guide section 36 and the shutter section 39) to perform the above-described preparation and (ii) the lift mechanism 44 to perform the contact operation in the step S102. The control of the unit controller 15 to cause the sucking pulling mechanism to perform the preparation is equivalent to third control of the present invention. The control of the unit controller 15 to cause the lift mechanism 44 to perform the contact operation is equivalent to second control of the present invention. The details of the step S102 will be given later.
[0058]
After the step S102, the unit controller 15 controls the yarn processing execution section 12 and the winding section 13 to guide the upper yarn Y2 and the lower yarn Y1 to the yarn joining device 33 (step S103). To be more specific, as described above, the unit controller 15 controls the drum driving motor 43 and the arm motor 38 to guide the upper yarn Y2 sucked and captured by the suction port 36c to the yarn joining device 33. The unit controller 15 also controls the arm motor 37 to guide the lower yarn Y1 sucked and captured by the suction port 35c to the yarn joining device 33.
[0059]
Subsequently, the unit controller 15 controls the yarn joining device 33 to join the upper yarn Y2 and the lower yarn Y1 together (step S104). Finally, the unit controller 15 controls the winding section 13 to restart the winding operation (step S105).
[0060]
(Details of Preparation, etc.)
The following will detail the above-described step S102 with reference to FIG. 9. To begin with, for example, the unit controller 15 performs the following two processes in parallel upon receiving the detection signal described above. Hereinafter, these two processes will be referred to as the first process and the second process for the sake of convenience.
[0061]
The following describes the first process. To begin with, the unit controller 15 causes the lift mechanism 44 to move the package P up (the above-described distancing operation; step S201). Subsequently, for example, the unit controller 15 controls the drum driving motor 43 to stop the rotation of the traversing drum 42 and controls the brake section 45 to stop the rotation of the package P. The unit controller 15 determines whether the traversing drum 42 stops rotating based on a detection result by, e.g., the above-described rotary encoder (not illustrated; step S202). The unit controller 15 waits (NO in the step S202) until, e.g., the traversing drum 42 stops rotating. After the traversing drum 42 stops rotating, the shift to the next step occurs (YES in the step S202). The unit controller 15 determines whether the package P stops rotating based on a detection result by, e.g., the above-described rotation number sensor (not illustrated; step S203). The unit controller 15 waits (NO in the step S203) until, e.g., the package P stops rotating. After the package P stops rotating, the shift to the next step occurs (YES in the step S203). After both the traversing drum 42 and the package P stop rotating, the unit controller 15 controls the lift mechanism 44 to start the contact operation (step S204). The above-described steps are included in the first process. The order of the steps S202 and S203 may be reversed. Alternatively, the unit controller 15 may perform the steps S202 and S203 in parallel.
[0062]
The following describes the second process. The unit controller 15 causes the yarn processing execution section 12 to start at least a part of the preparation in parallel with the first process. To be more specific, for example, the unit controller 15 controls (drives) the arm motor 38 of the upper yarn capturing guide section 36 to cause the suction port 36c to start moving from the standby position to the suction position (step S205). In other words, the unit controller 15 starts at least a part (the second preparation in the present embodiment) of the preparation before the surface Pa of the package P makes contact with the outer circumferential surface 42b of the traversing drum 42. As such, by starting the preparation before the completion of the contact operation, the time required from the disconnection of the yarn Y to the completion of the yarn joining is restrained from becoming long as much as possible.
[0063]
In the unit controller 15 of the present embodiment, for example, a specific timing of start of the second preparation is set in advance as below. For example, this timing may be set at substantially the same time as the completion of the distancing operation by the lift mechanism 44 or set at a time when a predetermined time passes from the completion of the distancing operation. Alternatively, this timing may be set at a time which is after the disconnection of the running yarn Y and which is before or at the same time as the start of the distancing operation by the lift mechanism 44. Alternatively, this timing may be set at substantially the same time as the stop of rotation of the traversing drum 42 and/or the package P. Alternatively, this timing may be set at a time when a predetermined time passes from the stop of rotation of the traversing drum 42 and/or the package P.
[0064]
After the first and second processes, the unit controller 15 performs the following steps. For example, while taking a timing of start of the second preparation into consideration, the unit controller 15 drives the arm motor 38 so that the movement of the suction port 36c to the suction position is completed after the start of the contact operation and before the completion of the contact operation (step S206). Any detection means may detect that the suction port 36c reaches the suction position. For example, an unillustrated sensor configured to detect the suction port 36c may be provided. Alternatively, the arm motor 38 may be provided with an unillustrated rotary encoder. Alternatively, the unit controller 15 may determine that the suction port 36c reaches the suction position, after a predetermined time passes from the start of control by the arm motor 38.
[0065]
After the movement of the suction port 36c to the suction position has been completed, the surface Pa of the package P makes contact with the outer circumferential surface 42b of the traversing drum 42 so that the contact operation is completed (step S207). The completion of the contact operation may be detected by any detection means. Alternatively, the unit controller 15 may determine that the contact operation is completed, after a predetermined time passes from the start of the contact operation.
[0066]
After that, the unit controller 15 controls the shutter motor 39b to open the shutter 39a (step S208; the above-described first preparation). Because of this, after the contact operation of the package P is completed, the preparation is completed so as to enable the above-described sucking pulling operation. In other words, the unit controller 15 causes the first preparation to be completed after the surface Pa of the package P makes contact with the outer circumferential surface 42b of the traversing drum 42. As a result, the unit controller 15 causes the third control to be completed.
[0067]
As such, the unit controller 15 drives the shutter motor 39b so that the preparation is completed after the completion of the contact operation. This restrains the yarn end Ye from going through the gap G formed between the slackened yarn layer and the surface Pa.
[0068]
The unit controller 15 may be set to necessarily cause the yarn processing execution section 12 to perform the preparation in the case where the yarn Y is disconnected during the winding operation. In this case, however, the time required from the disconnection of the yarn Y to the completion of the yarn joining may always become disadvantageously long. Therefore, for example, the unit controller 15 preferably performs the third control only in the case where the running yarn Y is disconnected while the unit controller 15 controls the winding section 13 to increase the circumferential speed of the package P (i.e., to accelerate the package P). When the circumferential speed of the package P is increased, the circumferential speed of the package P and the traversing speed of the yarn Y are lower than the respective target speeds. When the yarn Y is disconnected while the circumferential speed of the package P is still low, the package P stops rotating in a shorter time than in the case where the yarn Y is disconnected while the circumferential speed of the package P is sufficiently high (i.e., the circumferential speed thereof reaches the target speed). The following will describe a problem which may occur in this case. Typically, tension is applied to the running yarn Y wound by the winding section 13. When the running yarn Y is disconnected, this tension moves the yarn end Ye of the yarn Y on the package P side to leap toward the package P side. As described above, when the running yarn Y is disconnected, a part of the yarn Y on the package P side is wound onto the package P until the rotation of the package P stops. However, when the package P stops rotating in a short time as described above, the circumferential speed of the package P becomes considerably low before the yarn end Ye of the yarn Y on the package P side is wound. In this case, the yarn end Ye is less likely to be wound onto the package P. The above-described movement of the yarn end Ye may not stop so that a part of the yarn Y is also slackened. This part of the yarn Y is close to the yarn end Ye, and has been already wound onto the package P. As such, when the yarn Y is disconnected while the circumferential speed of the package P is still low, the slackened yarn layer tends to be formed. As a result, the gap G is easily formed between the slackened yarn layer and the surface Pa of the package P, and thus the yarn end Ye of the yarn Y on the package P side is highly likely to go through the gap G. In the present embodiment, the third control is performed in such a case so that the yarn end Ye of the yarn Y on the package P side is effectively restrained from going through the gap G. When the circumferential speed of the package P is sufficiently high, all part of the yarn Y on the package P side is sufficiently wound onto the package P in a period between the disconnection of the yarn Y and the stop of rotation of the package P. Therefore, the yarn Y which is disconnected and slackened is less likely to be wound onto the package P. The unit controller 15 thus may cause the preparation to be completed before, e.g., the completion of the contact operation in the case where the highly-tensioned yarn Y is disconnected. This suppresses a risk that the yarn end Ye of the yarn Y on the package P side goes through the gap G, and shortens the time required from the disconnection of the yarn Y and the completion of the yarn joining.
[0069]
As described above, the preparation is started before the surface Pa of the package P moved up by the lift mechanism 44 makes contact with the outer circumferential surface 42 of the traversing drum 42 again. This suppresses an extremely late start of the sucking pulling operation. It is therefore possible to restrain the time required from the disconnection of the yarn Y to the completion of the yarn joining from becoming long, as much as possible. The preparation is completed after the completion of the contact operation. This suppresses the movement of the yarn end Ye before the package P makes contact with the traversing drum 42. It is therefore possible to restrain the yarn end Ye of the yarn Y on the package P side from going through the gap G formed between the slackened yarn layer and the surface Pa of the package P. As such, the time required from the disconnection of the yarn Y to the completion of the yarn joining is restrained from becoming long as much as possible, and the yarn end Ye of the yarn Y on the package P side is restrained from going through the gap G formed between the slackened yarn layer and the surface Pa of the package P.
[0070]
As described above, the unit controller 15 preferably performs the third control in the case where the running yarn Y is disconnected while the unit controller 15 controls the winding section 13 to increase the circumferential speed of the package P. This effectively restrains the yarn end Ye of the yarn Y on the package P side from going through the gap G as described above. Furthermore, this further restrains the time required from the disconnection of the yarn Y to the completion of the yarn joining from becoming long.
[0071]
The unit controller 15 is configured to drive the shutter section 39 in the third control so that the first preparation is completed after the completion of the second control. This suppresses the occurrence of high negative pressure at the suction port 36c before the completion of the contact operation. It is therefore possible to effectively restrain the negative pressure from moving the yarn end Ye before the completion of the contact operation.
[0072]
The traversing drum 42 includes the traversing groove 42a. With this arrangement, the yarn Y is traversed along the traversing groove 42a. In this case, the yarn Y which is about to be wound onto the package P does not make contact with the outer circumferential surface 42b of the traversing drum 42. That is, the contact pressure is applied only to the yarn Y which has been wound onto the package P. Furthermore, when the running yarn Y is disconnected, the package P is distanced from the traversing drum 42 by the first control. Therefore, when (i) the yarn Y has been disconnected and (ii) a part of the yarn Y is still not wound onto the package P, this part of the yarn Y is not pressed onto the surface Pa of the package P. Therefore, this part of the yarn Y is highly likely to be included in the package P while being distanced from the surface Pa. As a result, the gap G is highly likely to be formed in the above-described case. The third control is therefore especially effective.
[0073]
The following will describe modifications of the above-described embodiment. The members identical with those in the embodiment above will be denoted by the same reference numerals and the explanations thereof are not repeated.
[0074]
(1) In the embodiment above, the second preparation is started before the completion of the contact operation. The first preparation is started after the completion of the contact operation. However, the disclosure is not limited to this. The following will describe an example of another control with reference to a flowchart of FIG. 10. FIG. 10 is a flowchart detailing a step S102 of this modification. As shown in FIG. 10, the unit controller 15 performs the first process (the above-described steps S201 to S204) in the same manner as in the embodiment above. In the second process, the unit controller 15 may control the shutter motor 39b to start opening the shutter 39a instead of controlling the arm motor 38 (step S209). That is, the unit controller 15 may start the first preparation before the completion of the contact operation. The unit controller 15 may control the shutter section 39 so that the shutter 39a finishes opening (the above-described step S210) before the completion of the contact operation of the package P (the above-described step S207). The unit controller 15 may control the arm motor 38 to move the suction port 36c upward after the completion of the contact operation (step S211). Such control allows the suction port 36c to avoid reaching the suction position before the completion of the contact operation. Therefore, even when the negative pressure is generated at the suction port 36c, the negative pressure is restrained from moving the yarn end Ye before the package P is subjected to the contact operation.
[0075]
(2) In the embodiment above, one of the first preparation and the second preparation is started before the completion of the contact operation. The other of the first preparation and the second preparation is started after the completion of the contact operation. However, the disclosure is not limited to this. The following will describe an example of another control with reference to a flowchart of FIG. 11. FIG. 11 is a flowchart detailing a step S102 of this modification. As shown in FIG. 11, the unit controller 15 performs the first process (the above-described steps S201 to S204) in the same manner as in the embodiment above. In the second process, the unit controller 15 may cause (i) the suction port 36c to start moving upward (the above-described step S205) and (ii) the shutter 39a to start opening (the above-described step S209). That is, the unit controller 15 may start both of the first preparation and the second preparation before the completion of the contact operation. The order of the steps S205 and S209 may be reversed. Alternatively, the unit controller 15 may start the steps S205 and S209 at substantially the same time. The unit controller 15 may cause (i) the upward movement of the suction port 36c to be completed (step S212) and (ii) the shutter 39a to finish opening (step S213) after the completion of the contact operation of the package P (the above-described step S207). That is, the unit controller 15 may drive the upper yarn capturing guide section 36 and the shutter section 39 so that the first preparation and the second preparation are completed after the completion of the contact operation. Alternatively, the unit controller 15 may cause the first preparation to be completed before the completion of the contact operation. The order of the steps S212 and S213 may be reversed. Alternatively, the unit controller 15 may start the first preparation and the second preparation at the time when the steps S212 and S213 occur at substantially the same time. As described above, the unit controller 15 drives the upper yarn capturing guide section 36 and the shutter section 39 so that (i) at least a part of the preparation is started before the completion of the contact operation and (ii) all of the preparation is completed after the completion thereof.
[0076]
(3) In the embodiment above, the preparation includes the first preparation and the second preparation. The preparation may further include another operation. For example, the automatic winder 1 includes the negative pressure source 102 (see FIG. 4) shared by the yarn winding units 2. The respective negative pressure sources (not illustrated) may be provided to correspond to the yarn winding units 2 in addition to or instead of the negative pressure source 102. In each yarn winding unit 2 of this case, a negative pressure source may be provided between the negative pressure source 102 and the shutter section 39 in, e.g., the flow direction of the air. Each negative pressure source may be, e.g., a known blower device. This blower device may operate in the case where the negative pressure is generated at the suction port 36c of a corresponding yarn winding unit 2 and may stop its operation in the case where the negative pressure is not generated at this suction port 36c. For example, the unit controller 15 may control the on and off of a power source of this blower device. The operation of the on and off of this blower device may be included in the preparation. In this Example, the opening-closing operation of the shutter section 39 may be replaced with the operation of on and off of this blower device.
[0077]
(4) The following will describe another modification with reference to FIG. 12(a) and FIG. 12(b). The yarn winding unit 2 may include an upper yarn capturing guide section 60 as shown in FIG. 12(a) and FIG. 12(b), instead of the above-described upper yarn capturing guide section 36. For example, the upper yarn capturing guide section 60 is connected to an end portion of the fluid path 101a on the upstream side in the flow direction of the air. The end portion of the fluid path 101a is provided with, e.g., an opening 101b on the upstream side in the flow direction. The upper yarn capturing guide section 60 may include the above-described axis 36a, arm 36b, and suction port 36c. Furthermore, for example, a base end portion of the arm 36b may be provided with an openable portion 61. The openable portion 61 may be rotatable together with the arm 36b. That is, the openable portion 61 may be movable in accordance with the arm motor 38. The openable portion 61 may include a lid 62a and an opening 62b. The lid 62a is able to open and close the opening 101b. The lid 62a is provided at a part of the openable portion 61 in a rotational circumferential direction of the openable portion 61. The opening 62b is provided at a part of the openable portion 61 so as to be positionally different from the lid 62a in the rotational circumferential direction of the openable portion 61. As shown in FIG. 12(a), for example, when the suction port 36c is provided at the standby position, the lid 62a closes the opening 101b (i.e., closes the fluid path 101a). When the suction port 36c is moved from the standby position to the suction position, a state in which the door 62a closes the opening 101b is released. In other words, when the suction port 36c is provided at the suction position as shown in FIG. 12(b), the suction port 36c is connected to the fluid path 101a via the opening 62b. That is, when the suction port 36c is provided at the suction position, the opening 101b is opened. As such, the openable portion 61 is configured to open the fluid path 101a in the case where the suction port 36c is provided at the suction position. In this modification, the preparation includes a movement operation in which the arm motor 38 moves the suction port 36c from the standby position to the suction position. In the third control, the unit controller 15 may drive the arm motor 38 so that (i) the movement operation is started before the completion of the contact operation and (ii) the movement operation is completed after the completion thereof. This avoids the case where the suction port 36c reaches the suction position before the completion of the contact operation, and suppresses the occurrence of the high negative pressure at the suction port 36c before the completion thereof. For example, please refer to a sliding cutter (not illustrated) which is similar to the openable portion 61 and which is described in Japanese Laid-Open Utility Model Publication No. S57-30255.
[0078]
(5) In the embodiment above, the package P is moved up and down with respect to the traversing drum 42 by the lift mechanism 44. However, the disclosure is not limited to this. For example, the traversing drum 42 may be movable with respect to the package P. That is, one or both of the package P and the traversing drum 42 may be movable as long as the package P and the traversing drum 42 are movable relative to each other.
[0079]
(6) In the embodiment above, the yarn Y is traversed by the traversing drum 42. However, the disclosure is not limited to this. For example, the winding section 13 may include an unillustrated traversing guide and an unillustrated roller instead of the traversing drum 42. This traversing guide may be provided as a member different from this roller. The traversing guide may be attached to, e.g., a leading end of an arm swung by an unillustrated motor and may be able to reciprocate in the left-right direction. Alternatively, the traversing guide may be attached to an endless belt instead of the arm. The traversing guide may be able to reciprocate as the endless belt reciprocates in a predetermined range. The roller is configured to rotate together with the package P while being in contact with the surface Pa of the package P. This roller is equivalent to the contact roller of the present invention. The roller may be configured to cause the package P to be passively rotated in the same manner as the traversing drum 42. Alternatively, the package P may be rotated by an unillustrated motor. That is, the roller may be configured to rotate in accordance with the package P.
[0080]
(7) In the embodiment above, the unit controller 15 is configured to control each yarn winding unit 2. However, the disclosure is not limited to this. For example, the machine controller 4 may be able to control the yarn winding units 2. In this case, the machine controller 4 is equivalent to the control unit of the present invention while the automatic winder 1 is equivalent to the yarn winder of the present invention.
[0081]
(8) The present invention is applicable not only to the automatic winder 1 but also to a known air spinning machine, an open-end spinning machine (not illustrated), etc.
, Claims:We claim:

1. A yarn winder (2) comprising: a yarn supply section (11) which is able to supply a yarn (Y); a winding section (13) configured to perform a winding operation of forming a package (P) by winding the yarn (Y) supplied from the yarn supply section (11); a yarn connection mechanism (12, 13) configured to connect parts of the disconnected yarn (Y) in a case where the yarn (Y) is disconnected between the yarn supply section (11) and the winding section (13); and a control unit (15),
the winding section (13) including:
a contact roller (42) configured to rotate together with the package (P) while being in contact with a surface (Pa) of the package (P); and
a lift mechanism (44) which is able to perform (i) a distancing operation of distancing the surface (Pa) of the package (P) from an outer circumferential surface (42b) of the contact roller (42) and (ii) a contact operation of bringing the surface (Pa) of the package (P) into contact with the outer circumferential surface (42b) of the contact roller (42),
the yarn connection mechanism (13) including
a sucking pulling mechanism (36, 39) which is able to perform a sucking pulling operation of sucking and capturing a yarn end (Ye) of the disconnected yarn (Y) on the winding section (13) side by means of a suction port (36c) and pulling the yarn end (Ye) out from the package (P) rotating in a reverse direction as compared to the winding operation,
the control unit (15) being able to perform:
first control of causing the lift mechanism (44) to perform the distancing operation in the case where the yarn (Y) is disconnected between the yarn supply section (11) and the winding section (13);
second control of causing the lift mechanism (44) to perform the contact operation after the first control; and
third control of causing the sucking pulling mechanism (36, 39) to perform a predetermined preparation so as to enable the sucking pulling operation,
the sucking pulling mechanism (36, 39) being driven in the third control so that (i) the preparation is started before the completion of the contact operation performed in the second control and (ii) the preparation is completed after the completion of the contact operation.

2. The yarn winder (2) as claimed in claim 1, wherein, when the running yarn (Y) is disconnected while the control unit (15) controls the winding section (13) to increase the circumferential speed of the package (P), the control unit (15) performs the third control.

3. The yarn winder (2) as claimed in claim 1 or 2, wherein the sucking pulling mechanism (36, 39) includes:
a fluid path (101a) connecting the suction port (36c) to a sucking power source (102) configured to generate negative pressure at the suction port (36c); and
a shutter section (39) which is able to open and close the fluid path (101a),
the preparation includes a first preparation in which the shutter section (39) opens the fluid path (101a), and
the control unit (15) is configured to drive the shutter section (39) so that, in the third control, the first preparation is completed after the completion of the contact operation.

4. The yarn winder (2) as claimed in one of claims 1 to 3, wherein the sucking pulling mechanism (36, 39) includes
a movement mechanism (38) configured to move the suction port (36c) between a predetermined standby position and a suction position which is closer to the package (P) than the standby position is and which is provided for sucking the yarn end (Ye),
the preparation includes a second preparation in which the movement mechanism (38) moves the suction port (36c) from the standby position to the suction position, and
the control unit (15) is configured to drive the movement mechanism (38) so that, in the third control, the second preparation is completed after the completion of the contact operation.

5. The yarn winder (2) as claimed in claim 1 or 2, wherein the sucking pulling mechanism (36, 39) includes:
a movement mechanism (38) configured to move the suction port (36c) between a predetermined standby position and a suction position which is closer to the package (P) than the standby position is and which is provided for sucking the yarn end (Ye);
a fluid path (101a) connecting the suction port (36c) to a sucking power source (102) configured to generate negative pressure at the suction port (36c); and
an openable portion (61) which is configured to close the fluid path (101a) in accordance with the movement mechanism (38) in a case where the suction port (36c) is provided at the standby position, and to open the fluid path (101a) in accordance with the movement mechanism (38) in a case where the suction port (36c) is provided at the suction position,
the preparation includes a movement operation of moving the suction port (36c) from the standby position to the suction position, and
the control unit (15) is configured to drive the movement mechanism (38) so that, in the third control, the movement operation is completed after the completion of the contact operation.

6. The yarn winder (2) as claimed in one of claims 1 to 5, wherein the contact roller (42) includes a traversing groove (42a) which is formed on the outer circumferential surface (42b) of the contact roller (42) and which is provided for traversing the running yarn (Y).