Claims:We claim:
1. A yarn winding device (2) configured to perform winding process in which a package (P) is formed by winding a yarn that is pulled from a supply bobbin (Bs), comprising:
a tension applying device (31) that includes a resistance applying section (31a and 31b) capable of applying a resistance to the yarn running toward the package side in a yarn running direction;
a yarn joining device (32) that joins a yarn end of a first yarn and a yarn end of a second yarn when the yarn disconnects into the first yarn on the supply bobbin side running in the yarn running direction and the second yarn on the package side, and is arranged on the package side as compared to the tension applying device (31) in the yarn running direction;
a first yarn guiding device (34) that guides the first yarn toward the yarn joining device (32); and
a control section (15) that performs
a guiding control in which the control section (15) controls the first yarn guiding device (34) to guide the first yarn to the tension applying device (31) and the yarn joining device (32), and
a yarn tension control in which the control section (15) controls at least one between the tension applying device (31) and the first yarn guiding device (34) to pull a portion of the first yarn guided to the yarn joining device (32) that is present on downstream side in the yarn running direction as compared to the tension applying device (31).

2. The yarn winding device (2) as claimed in Claim 1, wherein
the first yarn guiding device (34) includes a holding section (34c) that holds the first yarn and a movement driving section (34d) that moveably drives the holding section (34c), and
during the yarn tension control, the control section (15) controls the movement driving section (34d) to cause the holding section (34c) to move from a predetermined first position to a second position, wherein a distance between the second position and the resistance applying section (31a and 31b) is longer than a distance between the first position and the resistance applying section (31a and 31b).

3. The yarn winding device (2) as claimed in Claim 2, wherein the holding section (34c) includes a sucking / catching member (51) that sucks and catches the first yarn, and a clamp portion (52) that clamps the first yarn that is sucked and caught by the sucking / catching member (51).

4. The yarn winding device (2) as claimed in one of Claims 1 to 3, wherein
the tension applying device (31) is configured so as to be switchable between at least a first tension state in which a predetermined resistance can be applied to the running yarn and a second tension state in which a stronger resistance as compared to the predetermined resistance can be applied to the running yarn, and
the control section (15) sets the tension applying device (31) to the first tension state during the winding process, and sets the tension applying device (31) to the second tension state during the yarn tension control.

5. The yarn winding device (2) as claimed in Claim 4, wherein the control section (15) can switch the state of the tension applying device (31) to the second tension state after the guiding control is completed and before starting the yarn tension control.

6. The yarn winding device (2) as claimed in one of Claims 1 to 5, wherein the yarn joining device (32) is a disc splicer (32) that is configured so as to position the first yarn and the second yarn between two discs and intertwine the first yarn and the second yarn.

7. The yarn winding device (2) as claimed in one of Claims 1 to 5, wherein the yarn joining device (32) is a knotter that is configured to knot the first yarn and the second yarn.

8. The yarn winding device (2) as claimed in one of Claims 1 to 7 comprising a pull resistance section (24) that applies a resistance against the pulling of the first yarn from the supply bobbin (Bs) while the guiding control is being performed.

9. A yarn guiding method used in a yarn winding device (2), the yarn winding device (2) comprising:
a tension applying device (31) that includes a resistance applying section (31a and 31b) that applies a resistance to a yarn running toward a package side in a yarn running direction;
a yarn joining device (32) that joins a yarn end of a first yarn and a yarn end of a second yarn when the yarn disconnects into the first yarn on a supply bobbin side running in the yarn running direction and the second yarn on the package side, and is arranged on the package side as compared to the tension applying device (31) in the yarn running direction;
a first yarn guiding device (34) that guides the first yarn toward the yarn joining device (32); and
a control section (15), wherein
the yarn guiding method includes
a guiding step in which the control section (15) controls the first yarn guiding device (34) to guide the first yarn to the tension applying device (31) and the yarn joining device (32), and
a yarn tension step in which the control section (15) controls at least one between the tension applying device (31) and the first yarn guiding device (34) to pull a portion of the first yarn guided to the yarn joining device (32) that is present on downstream side in the yarn running direction as compared to the tension applying device (31).

10. The yarn guiding method as claimed in Claim 9, wherein, during the yarn tension control, the first yarn guiding device (34) controls a movement driving section (34d) to cause a holding section (34c) to move from a predetermined first position to a second position, wherein a distance between the second position and the resistance applying section (31a and 31b) is longer than a distance between the first position and the resistance applying section (31a and 31b).
, Description:BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a yarn winding device and a yarn guiding method.

2. Description of the Related Art
The yarn winding device disclosed in each of Japanese Patent Applications Laid-Open Nos. 2017-088366 and 2012-001349 winds a yarn to form a package after pulling the yarn from a supply bobbin. When winding the yarn, tension is applied to the yarn with a tension applying device. Furthermore, if the yarn running between the supply bobbin and the package gets disconnected in the yarn running direction, the yarn winding device can join a yarn end of the yarn on the supply bobbin side (hereinafter, first yarn) and a yarn end of the yarn on the package side (hereinafter, second yarn). Specifically, the yarn winding device includes a yarn joining device that joins both the yarn ends, a relay pipe (first yarn guiding device) that guides the yarn on the supply bobbin side to the yarn joining device, and a suction mouth (second yarn guiding device) that guides the yarn on the package side to the yarn joining device. More specifically, the yarn joining device disclosed in Japanese Patent Application Laid-Open No. 2017-088366 is an air splicer that intertwines both the yarn ends by the action of the compressed air. The yarn joining device disclosed in Japanese Patent Application Laid-Open No. 2012-001349 is a disc splicer that intertwines both the yarn ends by sandwiching the yarns between two discs. As another yarn joining device, Japanese Patent Application Laid-Open No. 2018-159144 also discloses a knotter that mechanically knots both the yarn ends.
In recent years, for example, there has been a lot of development in the technology for winding yarns that can be easily stretched (stretchable yarns) that have core yarns made of synthetic fibers. One of the issues that arise when processing the stretchable yarn normally in a yarn winding device is as follows. For example, when the first yarn is guided to the yarn joining device by the first yarn guiding device, the first yarn may shrink and slacking may be generated in the yarn. If the yarn ends are joined together in a state in which the slacking has been generated, the shape and / or strength of the joint tends to become unstable.

Problem to be solved by the Invention
To solve such a problem, Japanese Patent Application Laid-Open No. 2017-088366 discloses a control means that can remove the slacking of the first yarn by using the yarn holding section provided in the air splicer and the first yarn guiding device explained above. Specifically, after the first yarn is guided to the yarn joining device by the first yarn guiding device, the relay pipe moves in a predetermined direction while the first yarn has been held in the yarn holding section. By doing so, a portion of the first yarn to be processed by the yarn joining device is stretched. As a result, both the yarn ends are joined in a state in which the slacking of the first yarn is removed, thus stabilizing the quality of the joint.
The yarn joining device disclosed in Japanese Patent Application Laid-Open No. 2012-001349 or Japanese Patent Application Laid-Open No. 2018-159144 does not include the yarn holding section present in Japanese Patent Application Laid-Open No. 2017-088366. Therefore, in the configuration having the yarn joining device, even when the relay pipe is moved in the predetermined direction explained above after the first yarn is guided to the yarn joining device, the first yarn is simply pulled out from the supply bobbin, resulting in slacking in the first yarn. Furthermore, installing a new yarn holding section in the yarn joining device disclosed in Japanese Patent Application Laid-Open No. 2012-001349 or Japanese Patent Application Laid-Open No. 2018-159144 would require additional manufacturing cost and development time.

SUMMARY OF THE INVENTION
An object of the present invention is to remove slacking of a yarn by using an existing device, that is, without providing a yarn holding section, in a yarn joining device of a yarn winding device.
According to one aspect of the present invention, a yarn winding device that is configured to perform winding process in which a package is formed by winding a yarn that is pulled from a supply bobbin, includes a tension applying device that includes a resistance applying section capable of applying a resistance to the yarn running toward the package side in a yarn running direction; a yarn joining device that joins a yarn end of a first yarn and a yarn end of a second yarn when the yarn disconnects into the first yarn on the supply bobbin side running in the yarn running direction and the second yarn on the package side, and is arranged on the package side as compared to the tension applying device in the yarn running direction; a first yarn guiding device that guides the first yarn toward the yarn joining device; and a control section. The control section performs a guiding control in which the control section controls the first yarn guiding device to guide the first yarn to the tension applying device and the yarn joining device, and a yarn tension control in which the control section controls at least one between the tension applying device and the first yarn guiding device to pull a portion of the first yarn guided to the yarn joining device that is present on downstream side in the yarn running direction as compared to the tension applying device.
According to another aspect of the present invention, a yarn guiding method is used in a yarn winding device that includes a tension applying device that includes a resistance applying section that applies a resistance to a yarn running toward a package side in a yarn running direction; a yarn joining device that joins a yarn end of a first yarn and a yarn end of a second yarn when the yarn disconnects into the first yarn on a supply bobbin side running in the yarn running direction and the second yarn on the package side, and is arranged on the package side as compared to the tension applying device in the yarn running direction; a first yarn guiding device that guides the first yarn toward the yarn joining device; and a control section. The yarn guiding method includes a guiding step in which the control section controls the first yarn guiding device to guide the first yarn to the tension applying device and the yarn joining device, and a yarn tension step in which the control section controls at least one between the tension applying device and the first yarn guiding device to pull a portion of the first yarn guided to the yarn joining device that is present on downstream side in the yarn running direction as compared to the tension applying device.
The above and other objects, features, advantages and technical and industrial significance of this invention will be better understood by reading the following detailed description of presently preferred embodiments of the invention, when considered in connection with the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a front view of an automatic winder according to one embodiment of the present invention.
FIG. 2 is a schematic front view of a winding unit.
FIG. 3 is a schematic side view of the winding unit.
FIG. 4A is an explanatory diagram showing an operation of a tension applying device.
FIG. 4B is another explanatory diagram showing the operation of the tension applying device.
FIG. 4C is still another explanatory diagram showing the operation of the tension applying device.
FIG. 5A is an explanatory diagram showing a configuration of and around a holding section of a first yarn guiding device.
FIG. 5B is another explanatory diagram showing a configuration of and around the holding section of the first yarn guiding device.
FIG. 5C is still another explanatory diagram showing a configuration of and around the holding section of the first yarn guiding device.
FIG. 5D is still another explanatory diagram showing a configuration of and around the holding section of the first yarn guiding device.
FIG. 6A is an explanatory diagram showing details of a yarn joining device.
FIG. 6B is another explanatory diagram showing details of the yarn joining device.
FIG. 6C is still another explanatory diagram showing details of the yarn joining device.
FIG. 7A is an explanatory diagram showing details of the yarn joining device.
FIG. 7B is another explanatory diagram showing details of the yarn joining device.
FIG. 8 is a flowchart of a process procedure performed by a unit controller.
FIG. 9A is an explanatory diagram explaining an operation of the first yarn guiding device.
FIG. 9B is another explanatory diagram explaining an operation of the first yarn guiding device.
FIG. 9C is still another explanatory diagram explaining an operation of the first yarn guiding device.
FIG. 9D is still another explanatory diagram explaining an operation of the first yarn guiding device.

DETAILED DESCRIPTION
Exemplary embodiments of the present invention are explained below. As shown in FIG. 1, a direction in which multiple winding units 2 are arranged is referred to as a horizontal direction. A direction that is perpendicular to the horizontal direction and a direction in which the gravitational force acts is referred to as an up-down direction (vertical direction). A direction orthogonal to both the horizontal direction and the up-down direction is referred to as a longitudinal direction. The direction in which a yarn Y runs is referred to as a yarn running direction.

Schematic configuration of an automatic winder
First, a schematic configuration of an automatic winder 1 of the present embodiment will be explained with reference to FIG. 1. FIG. 1 is a front view of the automatic winder 1 according to the present embodiment. The automatic winder 1 includes multiple winding units 2 (yarn winding devices of the present invention), a doffing device 3, and a main control device 4.
The winding units 2 are arranged along the horizontal direction. Each of the winding units 2 performs a winding process in which the yarn Y pulled from a supply bobbin Bs is wound onto a winding bobbin Bw (see FIG. 2) to form a package P. The yarn Y is a yarn that can be easily stretched (stretchable yarns) and has core yarns made of synthetic fibers. The doffing device 3 is arranged above the winding units 2, and is movable in the horizontal direction. Upon receiving a winding completion signal from a certain winding unit 2, the doffing device 3 travels to a position above the corresponding winding unit 2 to perform tasks such as removing the fully wound package P and mounting an empty winding bobbin Bw on the winding unit 2. The main control device 4 is arranged, for example, to the left side of the winding units 2. The main control device 4 is electrically connected to a unit controller 15 (explained later) of the winding unit 2 and a not-shown control section of the doffing device 3.

Winding Unit
Next, a configuration of the winding unit 2 will be explained with reference to FIGS. 2, 3, and 4A to 4C. FIG. 2 is a schematic front view of the winding unit 2. FIG. 3 is a schematic side view of the winding unit 2. FIGS. 4A to 4C are explanatory diagrams showing an operation of a tension applying device 31.
As shown in FIG. 2, the winding unit 2 includes a unit main body 10, a yarn supplying section 11, a yarn processing section 12, a winding section 13, and the unit controller 15 (control section of the present invention). The unit main body 10 is a columnar member that extends in the up-down direction. The yarn supplying section 11, the yarn processing section 12, and the winding section 13 are provided on a side surface of the unit main body 10. The yarn supplying section 11, the yarn processing section 12, and the winding section 13 are sequentially arranged in this order from the lower side to the upper side.
The yarn supplying section 11 is for unwinding the yarn Y from the supply bobbin Bs and supplying the yarn Y to the subsequent unit. The yarn supplying section 11 includes a supply bobbin supporting section 21 and a yarn unwinding assisting device 22. The supply bobbin supporting section 21 supports the supply bobbin Bs substantially vertically. The yarn unwinding assisting device 22 regulates, with a regulating cylinder 23, the bulging that occurs when the yarn Y is unwound from the supply bobbin Bs. In one embodiment, the regulating cylinder 23 can travel downward as the amount of the yarn wound on the supply bobbin Bs decreases so as to maintain a constant size of the bulge. A not-shown yarn feeler to detect the presence or absence of the running yarn is provided above the yarn unwinding assisting device 22.
As shown in FIG. 2, a kink preventer 24 (pull resistance section of the present invention) is provided near the yarn unwinding assisting device 22. The kink preventer 24 prevents the yarn Y from being excessively pulled from the supply bobbin Bs during the yarn joining operation explained later. The kink preventer 24 includes a brush 24a arranged at a tip end of an arm and a driving section 24b for rotationally driving the arm. The brush 24a, for example, is pivotable with the up-down direction as a pivoting shaft direction. The brush 24a is movable between a predetermined retracted position and a contact position in which the brush 24a comes into contact with an upper end of the supply bobbin Bs. The driving section 24b includes, for example, a solenoid that rotatably drives the arm.
The yarn processing section 12 is configured to perform predetermined processing on the yarn Y. The yarn processing section 12 includes the tension applying device 31, a yarn guiding device 32, and a yarn clearer 33.
The tension applying device 31 is configured to apply predetermined tension to the running yarn Y. The tension applying device 31 is a known device such as, for example, disclosed in Japanese Patent Application Laid-Open No. 2017-088366. The tension applying device 31 is arranged, for example, directly above the yarn supplying section 11. In other words, the yarn Y runs upwards along the up-down direction from the yarn supplying section 11 to the tension applying device 31. The tension applying device 31 is a so-called gate type device. As shown in FIG. 2, the tension applying device 31 includes multiple fixed gate members 31a and multiple movable gate members 31b. The fixed gate members 31a and the movable gate members 31b are arranged alternately in the up-down direction. The fixed gate members 31a and the movable gate members 31b extend along the longitudinal direction and are cantilevered with the end portion as the base end.
The movable gate members 31b can be switched between a tension applied state (see a solid line in FIGS. 2 and 4B) and a guidable state (see a dashed line in FIGS. 2 and 4A). When the movable gate members 31b are in the tension applied state, as explained later, tension is applied onto the yarn Y. When the movable gate members 31b are in the guidable state, the yarn Y can be guided through the fixed gate members 31a and the movable gate members 31b (explained in detail later). For example, as shown in FIG. 2, in the tension applied state, the movable gate members 31b are positioned to the right side as compared with the fixed gate members 31a. In this state, the yarn Y mainly comes in contact with the left side of the fixed gate members 31a and the right side of the movable gate members 31b. In this state, the yarn Y is bent by the fixed gate members 31a and the movable gate members 31b. In this state, because the yarn Y runs while being in contact with the fixed gate members 31a and the movable gate members 31b, the fixed gate members 31a and the movable gate members 31b provide resistance due to a frictional force. Accordingly, tension is applied onto the yarn Y. Portions of the fixed gate members 31a and the movable gate members 31b that come in contact with the yarn Y correspond to a resistance applying section of the present invention. However, the moving direction of the movable gate members 31b against the fixed gate members 31a is not limited to a direction explained above. For example, the movable gate members 31b can be configured to move in the longitudinal direction. Alternatively, the movable gate members 31b can be configured to be rotatable, for example, around a not-shown pivoting shaft that extends in the up-down direction as the pivoting shaft direction. Accordingly, the movable gate members 31b can be configured to move in a diagonal direction (a direction having components of the horizontal direction and the longitudinal direction). In other words, the movable gate members 31b can be configured to move in a desired direction as long as the state of the movable gate members 31b can be switched between the tension applied state and the guidable state.
Furthermore, the tension applying device 31 can change the strength of the tension by changing the position of the movable gate members 31b. In other words, when the movable gate members 31b, for example, move significantly to the right side, the bending angle of the yarn Y becomes larger (as explained above, the movement direction is not limited to such a direction). Such an action increases the contact length between the yarn Y, and the fixed gate members 31a and the movable gate members 31b. Accordingly, the frictional force (resistance) applied to the yarn Y by the fixed gate members 31a and the movable gate members 31b increases, resulting in increase in the tension. For example, the tension applying device 31 can be switched between a state shown in FIG. 4B (first tension state) and a state shown in FIG. 4C (second tension state). The contact length when the tension applying device 31 is in the second tension state is longer than the contact length when the tension applying device 31 is in the first tension state. Accordingly, the resistance applied on the yarn Y when the tension applying device 31 is in the second tension state becomes stronger as compared with a predetermined resistance applied on the yarn Y when the tension applying device 31 is in the first tension state.
On the other hand, in the guidable state, the movable gate members 31b are positioned on the left side as compared with the fixed gate members 31a. In this state, the yarn Y does not contact at least the movable gate members 31b. In this state, the yarn Y can be guided to the tension applying device 31 from a front side of the tension applying device 31. Thus, in the guidable state, no tension is applied to the yarn Y.
When the yarn Y running between the yarn supplying section 11 and the winding section 13 gets disconnected, the yarn joining device 32 joins the yarn Y on the yarn supplying section 11 side (hereinafter, first yarn Y1) and the yarn Y on the winding section 13 side (hereinafter, second yarn Y2). The yarn Y gets disconnected between the yarn supplying section 11 and the winding section 13 in the following cases. For example, when the yarn Y is cut by a cutter 33a after a yarn defect is detected by a yarn clearer 33 explained later, when the yarn Y is broken during the winding process, or when the yarn Y is completely unwound from the supply bobbin Bs. A more specific configuration of the yarn joining device 32 will be explained later.
A first yarn guiding device 34 that guides the first yarn Y1 to the yarn joining device 32 and a second yarn guiding device 35 that guides the second yarn Y2 to the yarn joining device 32 are provided near the yarn joining device 32. Broadly speaking, in the winding unit 2, after the first yarn guiding device 34 guides the first yarn Y1 to the yarn joining device 32 and the second yarn guiding device 35 guides the second yarn Y2 to the yarn joining device 32, the yarn joining device 32 joins a yarn end of the first yarn Y1 and a yarn end of the second yarn Y2. In the following explanation, a series of operations performed by the first yarn guiding device 34, the second yarn guiding device 35, and the yarn joining device 32 will be referred to as a "yarn joining operation". In the yarn joining operation, an operation in which the first yarn guiding device 34 guides the first yarn Y1 to the yarn joining device 32 and an operation in which the second yarn guiding device 35 guides the second yarn Y2 to the yarn joining device 32 are referred to as "preparatory operation". An operation after the preparatory operation in which the yarn joining device 32 joins the yarn end portion of the first yarn Y1 and the yarn end portion of the second yarn Y2 is referred to as a "joint forming operation". The yarn joining operation includes the preparatory operation and the joint forming operation.
The first yarn guiding device 34 is arranged below the yarn joining device 32 and near the tension applying device 31. The first yarn guiding device 34 is, for example, a known device such as that disclosed in Japanese Patent Application Laid-Open No. 2017-088366. The first yarn guiding device 34 performs a part of the preparatory operation. More specifically, the first yarn guiding device 34 includes a pipe-shaped arm 34b that is pivotable around a pivoting shaft 34a, a holding section 34c arranged at a tip end part of the arm 34b, and an arm driving motor 34d (movement driving section of the present invention) that rotatably drives the arm 34b. The axial direction of the pivoting shaft 34a is substantially parallel to the horizontal direction. The pivoting shaft 34a is arranged, for example, at a higher level as compared with the tension applying device 31. The arm 34b is a pipe-shaped member that is bent in a substantially U shape. The arm 34b at least extends in a direction orthogonal to the horizontal direction (see FIG. 3). The arm 34b is arranged such that the movement range of the holding section 34c includes a position that is at a lower level than the tension applying device 31 (shown by solid line in FIG. 2) and a position that is at a higher level than the tension applying device 31 (see FIG. 2). In other words, the holding section 34c is movable between a position that is at a lower level than the tension applying device 31 (shown by solid line in FIG. 2) and a position above the tension applying device 31 (see FIG. 2). The arm driving motor 34d is configured to move and drive the holding section 34c by swiveling and driving the arm 34b. The arm driving motor 34d is electrically connected to the unit controller 15 and is controlled by the unit controller 15.
A more specific configuration of the holding section 34c will be explained with reference to FIGS. 5A to 5D. FIGS. 5A to 5D are explanatory diagrams showing the configuration of and around the holding section 34c of the first yarn guiding device. As shown in FIGS. 5A to 5D, the holding section 34c includes a suction member 51 (the sucking / catching member of the present invention) and a cover member 52 (clamp portion of the present invention). The suction member 51 includes a suction port 51a connected to a not-shown negative pressure source via the arm 34b. The suction member 51 sucks and catches the yarn end of the first yarn Y1 with a negative pressure generated by the negative pressure source. The cover member 52 is capable of opening and closing the suction port 51a, and is capable of clamping the first yarn Y1 that is sucked and caught by the suction member 51. The cover member 52 is rotatably attached to the suction member 51 with the pivoting shaft 52a as a fulcrum. The cover member 52 includes a lid 52b that rotates to open and close the suction port 51a with pivoting shaft 52a as its fulcrum. The lid 52b is biased so as to close the suction port 51a, for example, by a not-shown spring. Moreover, the lid 52b can clamp the first yarn Y1 by positioning the yarn Y1 between the lid 52b and the suction member 51.
Furthermore, the cover member 52 includes, for example, a protrusion 52c and a side surface 52d. The protrusion 52c can contact a cam 53 (see FIGS. 3, 5A, and 5B) attached to the unit main body 10. When the protrusion 52c is in contact with the cam 53 from the front side, the arm 34b is moved and driven by the arm driving motor 34d, causing the cam 53 to rotate the cover member 52. Accordingly, the state of the cover member 52 is switched between a closed state in which the suction port 51a is closed (see FIG. 5A) and an open state in which the suction port 51a is open (see FIG. 5B). When the cover member 52 is in the closed state, the first yarn Y1 is clamped between the cover member 52 and the suction member 51. When the holding section 34c is positioned on the lower side of the tension applying device 31 (shown by solid line in FIG. 3), the side surface 52d is positioned on the front side of the suction member 51 (see FIGS. 5A and 5B). When the holding section 34c is positioned on the upper side of the tension applying device 31 (shown by double-dashed line in FIG. 3), the side surface 52d is positioned on the back side of the suction member 51 (see FIGS. 5C and 5D). The side surface 52d can contact a cam 54 (see FIGS. 3, 5C and 5D) that is mounted on the unit main body 10. When the side surface 52d is in contact with the cam 54 from the front side, the arm 34b is moved and driven by the arm driving motor 34d, causing the cam 54 to rotate the cover member 52. Accordingly, the state of the cover member 52 is switched between a closed state (see FIG. 5C) and an open state (see FIG. 5D).
Next, referring again to FIGS. 2 and 3, the second yarn guiding device 35 includes a pipe-shaped arm 35b that is pivotable around the pivoting shaft 35a, a holding section 35c arranged at a tip end part of the arm 35b that holds a yarn end portion of the second yarn Y2 by sucking and catching, and an arm driving motor 35d that rotatably drives the arm 35b. With this configuration, the second yarn guiding device 35 can suck and catch the second yarn Y2 and guide the second yarn Y2 to the yarn joining device 32. Detailed explanation relating to the operation of the second yarn guiding device 35 is omitted.
The yarn clearer 33 acquires information about thickness of the running yarn Y, and detects presence / absence of a yarn defect based on this information. The cutter 33a is arranged near the yarn clearer 33. When a yarn defect is detected, the yarn clearer 33 causes the cutter 33a to cut the yarn Y and outputs a detection signal to the unit controller 15.
The winding section 13 is operative to form the package P by winding the yarn Y on the winding bobbin Bw. The winding section 13 includes a cradle 41, a traversing drum 42, and a drum driving motor 43. The cradle 41 rotatably supports the winding bobbin Bw (package P). A traverse groove 42a is formed on an outer peripheral surface of the traversing drum 42. The traversing drum 42 rotates and traverses the yarn Y at a predetermined width while the yarn Y is being traversed via the traverse groove 42a. When the traversing drum 42 rotates while being in contact with the package P formed on the winding bobbin Bw while traversing the yarn Y via the traverse groove 42a, the package P and winding bobbin Bw are driven and rotated by the action of the contact friction with the traversing drum 42. Accordingly, the yarn Y is wound around the winding bobbin Bw to form the package P.
The drum driving motor 43 can rotate and drive the traversing drum 42 in a direction in which the yarn Y is wound into the package P (forward direction) and a direction in which the yarn Y can be pulled from the package P (backward direction). In a normal winding process, the traversing drum 42 is driven forwards to rotate the package P forwards, winding the yarn Y onto the package P. However, during the yarn joining operation explained above, when the above preparatory operation is performed, the traversing drum 42 is driven in a reverse direction to reverse rotate the package P. As a result, the second yarn guiding device 35 pulls the second yarn Y2 near the yarn joining device 32.
The unit controller 15 is installed in the unit main body 10. The unit controller 15 includes a CPU, a ROM, and a RAM. The unit controller 15 controls various components of the winding unit 2 according to a computer program stored in the ROM by using the CPU.
In the winding unit 2 having the above configuration, the unit controller 15 drives the drum driving motor 43 while the package P is in contact with the traversing drum 42 to rotate the traversing drum 42. Accordingly, the yarn Y pulled from the supply bobbin Bs is wound onto the winding bobbin Bw to form the package P (winding process). When the yarn Y is disconnected into the first yarn Y1 and the second yarn Y2, the unit controller 15 controls each component of the winding unit 2 to perform the yarn joining operation (preparatory operation and joint forming operation).

Specific configuration of the yarn joining device
Next, a specific configuration of the yarn joining device 32 will be explained with reference to FIGS. 6A to 6C, 7A, and 7B. FIG. 6A is a plan view of the yarn joining device 32. FIG. 6B is a front view of the yarn joining device 32. FIG. 6C is a bottom view of the yarn joining device 32. FIG. 7A is a front view of a pair of discs 66 explained later. FIG. 7B is a cross-sectional view along a VII(b)-VII(b) line shown in FIG. 7A.
The yarn joining device 32 is, for example, a disc splicer known in the art. As shown in FIGS. 6A to 6C, the yarn joining device 32 includes a main body 61, a left cover 62, a right cover 63, an upper guiding plate 64, a lower guiding plate 65, a pair of discs 66 (66L, 66R), an upper yarn shifting lever 67, and a lower yarn shifting lever 68. Moreover, the yarn joining device 32 includes a not-shown cutter for cutting and removing an unwanted portion of the yarn end.
The main body 61 is a substantially rectangular parallelepiped member. The left cover 62 is affixed to a left front side of the main body 61. The right cover 63 is fixed to a right front side of the main body 61. In the horizontal direction, a gap 69 that extends in the longitudinal direction is formed between the left cover 62 and the right cover 63. The gap 69 is for guiding the first yarn Y1 and the second yarn Y2 during the yarn joining operation.
The upper guiding plate 64 is fixed to an upper surface of the main body 61. A first upper guiding groove 64a that guides the first yarn Y1 and a second upper guiding groove 64b that guides the second yarn Y2 are formed on the upper guiding plate 64. The first upper guiding groove 64a and the second upper guiding groove 64b are arranged directly above the gap 69. The lower guiding plate 65 is fixed to the lower surface of the main body 61. A first lower guiding groove 65a that guides the first yarn Y1 and a second lower guiding groove 65b that guides the second yarn Y2 are formed on the lower guiding plate 65. The first lower guiding groove 65a and the second lower guiding groove 65b are arranged directly above the gap 69.
The disks 66L and 66R are arranged so as to face each other in the horizontal direction. A gap secured between the disc 66L and the disc 66R at least partially overlaps the gap 69 explained above. During the yarn joining operation, the first yarn Y1 and the second yarn Y2 are guided between the disc 66L and the disc 66R in the horizontal direction (see FIGS. 7A and 7B). While the first yarn Y1 and the second yarn Y2 are placed between the discs 66L and 66R, the discs 66L and 66R can rotate and untwist the first yarn Y1 and the second yarn Y2 and intertwine the untwisted first yarn Y1 and the second yarn Y2.
The upper yarn shifting lever 67 and the lower yarn shifting lever 68 guide the first yarn Y1 guided by the first yarn guiding device 34 near the yarn joining device 32, and the second yarn Y2 guided by the second yarn guiding device 35 near the yarn joining device 32, into the gap 69. The upper yarn shifting lever 67 guides the first yarn Y1 to the first upper guiding groove 64a and guides the second yarn Y2 to the second upper guiding groove 64b. The lower yarn shifting lever 68 guides the first yarn Y1 to the first lower guiding groove 65a and guides the second yarn Y2 to the second lower guiding groove 65b. For further details on the structure and the like of the yarn joining device 32, Japanese Patent Application Laid-Open No. 2012-001349, for example, can be referred.
One of the issues that arises in the winding unit 2 when processing a stretchable yarn Y normally as explained above is as follows. That is, when the first yarn Y1 is guided to the yarn joining device 32 by the first yarn guiding device 34, the first yarn Y1 is likely to shrink and slacking of the yarn is likely to occur. If the yarn ends are joined together in a state in which the slacking has occurred, the shape and / or strength of the joint tends to become unstable. Therefore, it is necessary to remove the slacking of the stretchable yarn before joining the yarn ends. However, because the yarn joining device 32 (disc splicer) of the present embodiment is not provided with a yarn holding section provided in the air splicer disclosed in, for example, Japanese Patent Application Laid-Open No. 2017-088366, it is difficult to pull the first yarn Y1 by using the yarn joining device 32.
Just as a reference, for example, Japanese Patent Application Laid-Open No. 2017-065896 discloses a not-shown yarn accumulating device as a device for preventing slacking of the yarn. The yarn accumulating device can temporarily accumulate the produced yarn when the yarn is joined in a not-shown spinning unit in which the yarn is continuously generated by the spinning device. Such a configuration prevents the yarn from being supplied to a downstream side in the yarn running direction during the joining process, and prevents slacking of the yarn. In other words, this type of yarn accumulating device does not remove the slacking of the yarn itself.
In the present embodiment, the unit controller 15 of the winding units 2 performs the following control to remove slacking of the yarn Y by utilizing the existing devices even in a configuration in which a disk splicer is provided as the yarn joining device 32.

Control performed by the unit controller
Details of the control performed by the unit controller 15 will be explained mainly with reference to the flowchart shown in FIG. 8 and the explanatory diagrams shown in FIGS. 9A to 9D. The control performed by the unit controller 15 from the time when the yarn Y gets disconnected during the winding process to the time when the winding process is restarted will be explained below. The control refers to a control performed relating to the preparatory operation, and in particular, on the tension applying device 31 and the first yarn guiding device 34. Furthermore, a control in which the second yarn guiding device 35 guides the second yarn Y2 to the yarn joining device 32 is performed during the winding process between the time when the yarn Y is disconnected during the winding process and the time when the winding process is restarted; however, a detailed description of this control is omitted.
As an initial state, the unit controller 15 controls each component of the winding unit 2 to execute the winding process. During the winding process, the state of the tension applying device 31 is set to the first tension state. During the winding process, the holding section 34c of the first yarn guiding device 34 and the holding section 35c of the second yarn guiding device 35 are respectively placed at positions that do not interfere with the running yarn Y (waiting positions). More specifically, the waiting position of the holding section 34c is a position shown in FIG. 9A. When the holding section 34c is at the waiting position, the holding section 34c can immediately suck and catch the cut yarn Y (first yarn Y1) even when, for example, the yarn Y is unintentionally cut. When the holding section 34c is in the waiting position, the cover member 52 is operated by the cam 53 so such that the suction port 51a is open (see FIG. 5B). Accordingly, the first yarn Y1 can be sucked and caught by the suction member 51.
During the winding process, for example, when a yarn defect is detected by the yarn clearer 33, the yarn Y is cut by the cutter 33a and the yarn Y is disconnected into the first yarn Y1 and the second yarn Y2 (Step S101). Upon receiving a signal from the yarn clearer 33 indicating that the yarn Y has been cut, the unit controller 15 controls each component of the winding unit 2 to temporarily stop the winding process (Step S102). Next, the unit controller 15 controls the first yarn guiding device 34 so as to cause the holding section 34c to suck and catch the first yarn Y1 (Step S103). Alternatively, the sucking and catching operation can be performed before the winding process is completely stopped. Next, the unit controller 15 controls the tension applying device 31 to set the state of the tension applying device 31 to the guidable state explained above (Step S104; see FIG. 4A). That is, the unit controller 15 sets the state of the tension applying device 31 to the guidable state before the holding section 34c that has caught the first yarn Y1 is moved to the second position (Step S105 explained later). Step S104 can be performed before or at the same time as Step S103. Moreover, in parallel with or after performing Step S104, the unit controller 15 controls the kink preventer 24 so as to move the brush 24a from the retracted position to the contact position. Accordingly, a resistance is applied against the pulling of the first yarn Y1 from the supply bobbin Bs during a guiding control explained later.
Next, the unit controller 15 rotates the arm 34b by controlling the arm driving motor 34d, thereby moving the holding section 34c at a higher level than the tension applying device 31, and positioning the holding section 34c near the yarn joining device 32 (Step S105; see FIG. 9B). At this step, the suction port 51a is closed by the cover member 52, and the first yarn Y1 is placed between the cover member 52 and the suction member 51. In other words, the first yarn Y1 is clamped by the cover member 52 and the suction member 51. The position of the holding section 34c shown in FIG. 9B (guiding position; the first position of the present invention) is a position that is opposite to the first position in which the tension applying device 31 positioned therebetween in the up-down direction. By moving the holding section 34c to the guiding position, the first yarn Y1 is guided to the tension applying device 31 and the yarn joining device 32 (guiding control). More specifically, the first yarn Y1 is arranged between the fixed gate members 31a and the movable gate members 31b in the horizontal direction (shown by a double-dashed line in FIG. 4A). At Step S105, the first yarn Y1 is pulled from the supply bobbin Bs. The pulled first yarn Y1 (stretchable yarn) shrinks due to its elasticity and becomes slightly slackened (see FIG. 9B).
After executing the guiding control, the unit controller 15 controls the tension applying device 31. By such control, the state of the movable gate members 31b is switched from the guidable state to the second tension state (Step S106; see FIG. 4C). Accordingly, the first yarn Y1 is held by the fixed gate members 31a and the movable gate members 31b. When the tension applying device 31 is in the second tension state, the fixed gate members 31a and the movable gate members 31b apply a resistance to the first yarn Y1. The resistance applied on the first yarn Y1 when the tension applying device 31 is in the second tension state is stronger than the resistance applied on the first yarn Y1 when the tension applying device 31 is in the first tension state. The unit controller 15 switches the state of the movable gate members 31b to the second tension state before starting the yarn tension control explained later.
Next, the unit controller 15 rotates the arm 34b by controlling the arm driving motor 34d, and moves the holding section 34c to an extended position (second position of the present invention) that is behind the guiding position (Step S107). Compared with the distance between the guiding position and a section (resistance applying section) of the fixed gate members 31a and the movable gate members 31b that is in contact with the first yarn Y1, the distance between the resistance applying section and the extended position is longer. When the holding section 34c is moving from the guiding position to the extended position, a state in which the first yarn Y1 is clamped by the cover member 52 and the suction member 51 is maintained. Therefore, when the holding section 34c moves from the guiding position to the extended position, the portion of the first yarn Y1 clamped in the holding section 34c is prevented from slipping from the holding section 34c. Moreover, the tension applying device 31 (more specifically, the fixed gate members 31a and the movable gate members 31b) apply a resistance to the first yarn Y1. When the holding section 34c moves from the guiding position to the extended position, the portion of the first yarn Y1 that is in contact with the fixed gate members 31a and the movable gate members 31b is prevented from slipping. Therefore, when the holding section 34c moves from the guiding position to the extended position, the portion of the first yarn Y1 placed between the tension applying device 31 and the holding section 34c (that is, the portion of the tension applying device 31 at the downstream side of the yarn running direction) is stretched. Accordingly, the slacking of the first yarn Y1 guided to the yarn joining device 32 is removed. The yarn tension control for pulling the first yarn Y1 is performed at Step S107. The unit controller 15 controls the winding section 13 and the second yarn guiding device 35 to guide the second yarn Y2 to the yarn joining device 32 before the yarn tension control explained above is completed (detailed explanation is omitted).
Next, the unit controller 15 controls the yarn joining device 32 to join the yarn end of the first yarn Y1 and the yarn end of the second yarn Y2 (S108; joint forming operation). Moreover, at this step, the unit controller 15 operates the not-shown cutter provided in the yarn joining device 32 and cuts an unnecessary portion of the yarn end. Furthermore, the unit controller 15 controls the first yarn guiding device 34 to move the holding section 34c, and controls the cam 54 to move the cover member 52 so as to open the suction port 51a (see FIG. 5D). Accordingly, the unnecessary portion of the yarn from the yarn end of the first yarn Y1 is sucked and removed. Next, the unit controller 15 controls the first yarn guiding device 34 to return the holding section 34c to the waiting position (S109; see FIG. 9D). The same control is performed on the second yarn guiding device 35. Furthermore, the unit controller 15 causes the state of the movable gate member 31b of the tension applying device 31 to be switched from the second tension state to the first tension state (S110). Furthermore, Step S110 can be performed before or at the same time as Step S109. Moreover, in parallel with or after performing Step S110, the unit controller 15 controls the kink preventer 24 so as to move the brush 24a from the contact position to the retracted position. Lastly, the unit controller 15 controls each component of the winding unit 2 to restart the winding process (S111).
As explained above, by performing the yarn tension control, the first yarn Y1 guided to the yarn joining device 32 is pulled by the existing tension applying device 31 and the first yarn guiding device 34. Consequently, even in a configuration in which the yarn holding section that holds the yarn Y is not provided in the yarn joining device 32, slacking of the yarn Y can be removed by using the existing device.
Moreover, in the present embodiment, the yarn tension control can be performed by moving the existing movable holding section 34c. Accordingly, by effectively using the existing device, slacking of the first yarn Y1 can be removed.
Moreover, the first yarn Y1 can be clamped by the cover member 52. Accordingly, when the yarn tension control is performed, the first yarn Y1 can be prevented from slipping from the holding section 34c. Consequently, slacking of the first yarn Y1 can be reliably removed by performing the yarn tension control.
Moreover, during the yarn tension control, the unit controller 15 sets the state of the tension applying device 31 to the second tension state. Accordingly, during the yarn tension control, a strong resistance can be applied to the first yarn Y1. Accordingly, the first yarn Y1 can be prevented from slipping from the fixed gate member 31a or the movable gate member 31b. Therefore, the first yarn Y1 can be prevented from slacking again during the yarn tension control.
Moreover, after performing the guiding control and before starting the yarn tension control, the unit controller 15 switches the state of the tension applying device 31 to the second tension state. Therefore, slipping of the first yarn Y1 can be prevented efficiently.
Moreover, in the yarn joining device 32 (disc splicer) of the present embodiment, a holding section similar to that provided in a not-shown air splicer is not provided. Therefore, in the configuration in which the disc splicer is provided as the yarn joining device 32, the yarn tension control using the conventionally provided tension applying device 31 and the first yarn guiding device 34 is particularly effective.
Moreover, the first yarn Y1 can be prevented from being excessively pulled out from the supply bobbin Bs by the kink preventer 24 during the guiding control. Therefore, slacking of the first yarn Y1 can be prevented efficiently.
Modifications in which the above embodiment is modified will be explained below. However, parts and elements that are identical to the embodiment explained above are indicated by the same reference symbols and explanation thereof is omitted.
(1) In the embodiments explained above, the yarn joining device 32 is a disc splicer; however, the present invention is not limited to such a configuration. As a yarn joining device, for example, a knotter that mechanically knots the first yarn Y1 and the second yarn Y2 as explained in Japanese Patent Application Laid-Open No. 2018-159144 can be provided. Alternatively, as a yarn joining device, an air splicer as explained in Japanese Patent Application Laid-Open No. 2017-088366 can also be provided. Even in such configurations, slacking of the first yarn Y1 can be removed by performing the yarn tension control explained above.
(2) In the embodiments explained above, the state of the tension applying device 31 is switched to the second tension state (S106) before the yarn tension control (S107) is started; however, the present invention is not limited to such a configuration. For example, Steps S106 and S107 can be started at the same time.
(3) In the embodiments explained above, the state of the tension applying device 31 is switched to the guidable state (S104) before the guiding control (S105) is started; however, the present invention is not limited to such a configuration. For example, Steps S104 and S105 can be started at the same time. Alternatively, the winding unit 2 can be configured to guide the first yarn Y1 to the tension applying device 31 even when the tension applying device 31 is in the tension applied state. That is, for example, it is possible to provide on the front side of the tension applying device 31 a not-shown guide member configured to bend the first yarn Y1 that is moving backwards towards the tension applying device 31 in a wavelike shape.
(4) In the embodiments explained above, the state of the tension applying device 31 is switched to the second tension state before the yarn tension control (S107) is performed; however, the present invention is not limited to such a configuration. During the yarn tension control, the state of the tension applying device 31 can be switched, for example, to the first tension applying state (that is, a state that is same as that during winding process).
(5) In the embodiments explained above, the holding section 34c is capable of clamping the first yarn Y1; however, the present invention is not limited to this configuration. For example, the holding section 34c can be configured to simply suck and hold the first yarn Y1 without clamping the first yarn Y1.
(6) In the embodiments explained above, the holding section 34c includes a suction member 51 that sucks and catches the first yarn Y1. However, the present invention is not limited to such a configuration. Instead of the suction member 51, for example, a clamp member that is capable of clamping and catching the first yarn Y1 can be provided.
(7) In the embodiments explained above, the yarn tension control is performed by moving the holding section 34c; however, the present invention is not limited to such a configuration. For example, another approach would be to change the length of the yarn path by moving the movable gate members 31b of the tension applying device 31 in the horizontal direction. Accordingly, the first yarn Y1 can be extended by using such functions of the tension applying device 31 (the yarn tension control can be performed). Alternatively, for example, the tension applying device 31 itself can be configured to be movable against the unit main body 10. In other words, the yarn tension control can be performed by causing the tension applying device 31 to move against the holding section 34c. In such a configuration, both the holding section 34c and the tension applying device 31 can be caused to move. As explained above, the yarn tension control can be performed by controlling the tension applying device 31 and / or the first yarn guiding device 34.
(8) In the embodiment explained above, the winding unit 2 is provided with the kink preventer 24; however, the present invention is not limited to such a configuration. The kink preventer 24 need not be necessarily provided in the winding unit 2. In such a configuration, even when the first yarn Y1 is pulled excessively from the supply bobbin Bs during the guiding control, slacking of the first yarn Y1 can be prevented by performing the yarn tension control. Alternatively, even when the kink preventer 24 is not provided, the tension applying device 31, for example, can be configured in the following manner. The tension applying device 31 can be configured such that when the movable gate members 31b are in the second tension state, the first yarn Y1 is firmly positioned between the fixed gate members 31a and the movable gate members 31b. Accordingly, even when the first yarn Y1 is pulled excessively from the supply bobbin Bs during the guiding control, the first yarn Y1 can be pulled effectively during the yarn tension control. Therefore, slacking of the first yarn Y1 can be removed effectively.
(9) In the embodiments explained above, the winding unit 2 is provided with the gate type tension applying device 31; however, the present invention is not limited to such a configuration. The winding unit 2 can include a not-shown disc-type tension applying device that applies a resistance to the yarn Y by positioning the yarn Y between a plurality of a not-shown discs.
(10) The present invention is not limited to the winding unit 2 of the automatic winder 1, and can be applied to various yarn winding devices that pull yarn from the supply bobbin to form a package.
According to one aspect of the present invention, a yarn winding device that is configured to perform winding process in which a package is formed by winding a yarn that is pulled from a supply bobbin, includes a tension applying device that includes a resistance applying section capable of applying a resistance to the yarn running toward the package side in a yarn running direction; a yarn joining device that joins a yarn end of a first yarn and a yarn end of a second yarn when the yarn disconnects into the first yarn on the supply bobbin side running in the yarn running direction and the second yarn on the package side, and is arranged on the package side as compared to the tension applying device in the yarn running direction; a first yarn guiding device that guides the first yarn toward the yarn joining device; and a control section. The control section performs a guiding control in which the control section controls the first yarn guiding device to guide the first yarn to the tension applying device and the yarn joining device, and a yarn tension control in which the control section controls at least one between the tension applying device and the first yarn guiding device to pull a portion of the first yarn guided to the yarn joining device that is present on downstream side in the yarn running direction as compared to the tension applying device.
By performing the yarn tension control, the first yarn guided to the yarn joining device is pulled by the existing tension applying device and the first yarn guiding device. As a result, slacking of the first yarn can be removed. Consequently, even in a configuration in which a yarn holding section that holds a yarn is not provided in the yarn joining device, slacking of the yarn can be removed by using the existing device.
In the above yarn winding device, the first yarn guiding device includes a holding section that holds the first yarn and a movement driving section that moveably drives the holding section. During the yarn tension control, the control section controls the movement driving section to cause the holding section to move from a predetermined first position to a second position, wherein a distance between the second position and the resistance applying section is longer than a distance between the first position and the resistance applying section.
For example, it may be possible to perform the yarn tension control by configuring the entire tension applying device to be movable, however in this case, it is necessary to newly provide a moving mechanism for moving the entire tension applying device. In the present invention, the yarn tension control can be performed by moving the existing movable holding section. Accordingly, by effectively using the existing device, slacking of the first yarn can be removed.
In the above yarn winding device, the holding section includes a sucking / catching member that sucks and catches the first yarn, and a clamp portion that clamps the first yarn that is sucked and caught by the sucking / catching member.
For example, in a configuration in which the holding section has only the sucking / catching member, when the holding section moves during the yarn tension control, the first yarn may slip from the holding section. This may cause the first yarn to slacken. In the present invention, the caught first yarn can be clamped by the clamp portion. Accordingly, when the yarn tension control is performed, the first yarn can be prevented from slipping from the holding section. Consequently, slacking of the first yarn can be reliably removed by performing the yarn tension control.
In the above yarn winding device, the tension applying device is configured so as to be switchable between at least a first tension state in which a predetermined resistance can be applied to the running yarn and a second tension state in which a stronger resistance as compared to the predetermined resistance can be applied to the running yarn. The control section sets the tension applying device to the first tension state during the winding process, and sets the tension applying device to the second tension state during the yarn tension control.
If the first yarn slips from the resistance applying section during the yarn tension control, the first yarn may slacken by being pulled out from the supply bobbin. In the present invention, during the yarn tension control, a strong resistance can be applied to the first yarn. Accordingly, the first yarn can be prevented from slipping from the resistance applying section. Therefore, the first yarn can be prevented from slacking during the yarn tension control.
In the above yarn winding device, the control section can switch the state of the tension applying device to the second tension state after the guiding control is completed and before starting the yarn tension control.
If the yarn tension control is started after the guiding control but before switching the state of the tension applying device to the second tension state, the first yarn may slip from the resistance applying section. In contrast, in the present invention, slipping of the first yarn can be prevented efficiently.
In the above yarn winding device, the yarn joining device is a disc splicer that is configured so as to position the first yarn and the second yarn between two discs and intertwine the first yarn and the second yarn.
In the disc splicer, a yarn holding section similar to that provided in an air splicer is not provided. Therefore, in the configuration in which the disc splicer is provided as the yarn joining device, the yarn tension control using the conventionally provided tension applying device and the first yarn guiding device is particularly effective.
In the above yarn winding device, the yarn joining device is a knotter that is configured to knot the first yarn and the second yarn. In the knotter, a yarn holding section similar to that provided in an air splicer is not provided. Therefore, in the configuration in which the knotter is provided as the yarn joining device, the yarn tension control using the conventionally provided tension applying device and the first yarn guiding device is particularly effective.
The above yarn winding device includes a pull resistance section that applies a resistance against the pulling of the first yarn from the supply bobbin while the guiding control is being performed. The first yarn is pulled out from the supply bobbin during the guiding control. In the present invention, because it is possible to apply a resistance against the first yarn pulled out from the supply bobbin, the first yarn can be prevented from being excessively pulled out from the supply bobbin during the guiding control. Therefore, slacking of the first yarn can be prevented efficiently.
According to another aspect of the present invention, a yarn guiding method is used in a yarn winding device that includes a tension applying device that includes a resistance applying section that applies a resistance to a yarn running toward a package side in a yarn running direction; a yarn joining device that joins a yarn end of a first yarn and a yarn end of a second yarn when the yarn disconnects into the first yarn on a supply bobbin side running in the yarn running direction and the second yarn on the package side, and is arranged on the package side as compared to the tension applying device in the yarn running direction; a first yarn guiding device that guides the first yarn toward the yarn joining device; and a control section. The yarn guiding method includes a guiding step in which the control section controls the first yarn guiding device to guide the first yarn to the tension applying device and the yarn joining device, and a yarn tension step in which the control section controls at least one between the tension applying device and the first yarn guiding device to pull a portion of the first yarn guided to the yarn joining device that is present on downstream side in the yarn running direction as compared to the tension applying device. By performing the yarn guiding method of the present invention, the first yarn guided to the yarn joining device is pulled by the existing tension applying device and the first yarn guiding device. As a result, slacking of the first yarn can be removed. Consequently, even in a configuration in which a yarn holding section that holds a yarn is not provided in the yarn joining device, slacking of the yarn can be removed by using the existing device.
In the above yarn guiding method, during the yarn tension control, the first yarn guiding device controls a movement driving section to cause a holding section to move from a predetermined first position to a second position, wherein a distance between the second position and the resistance applying section is longer than a distance between the first position and the resistance applying section.
In the above explanation, the meaning of "a plurality of" also includes "a predetermined number of".
Although the invention has been explained with respect to specific embodiments for a complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art that fairly fall within the scope of the claims.