YARN WINDER

Abstract

 Exertion of a large force from a yarn to a fulcrum guide at the time of yarn threading is prevented. A yarn winder 10 includes a second guide unit 15b having a cylindrical fulcrum guide 16 and a yarn deposit guide 31 on which a yarn Y to be threaded to the fulcrum guide 16 is deposited while not making contact with the fulcrum guide 16, when the yarn Y sucked and held by a suction gun 60 is threaded to the fulcrum guide 16.

Description

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a yarn winder which includes a guide unit having a fulcrum guide functioning as a fulcrum when a yarn is wound onto a bobbin while being traversed.

[0002] A yarn winder configured to wind yarns spun out from a spinning apparatus onto bobbins while traversing the yarns has been known. In such a yarn winder, fulcrum guides that function as fulcrums for winding the yarns are provided. For example, in Patent Literature 1 (Japanese Laid-Open Patent Publication No. 2013-23787), roller-shaped fulcrum guides are provided, and yarns are placed on the outer circumferential surfaces of the fulcrum guides.

[0003] Among the fulcrum guides, there are, for example, fixed fulcrum guides each of which is arranged not to rotate about the central axis when yarns are wound, as described in Patent Literature 1.

SUMMARY OF THE INVENTION

[0004]  Yarn threading to such fulcrum guides is performed, for example, in such a way that an operator operates a sucking holding member (e.g., a suction gun) that sucks and holds yarns. When the yarns are sucked and held by the sucking holding member, the tension of the yarns is high as compared to a state in which the yarns are being wound. When yarn threading is performed for the fulcrum guides of the yarn winder, yarns threaded to fulcrum guides that are remote from a place where the operator operates the sucking holding member are significantly bended. When the yarns that are greatly tensioned due to the sucking and holding by the sucking holding member are threaded to the fulcrum guides, if the yarns making contact with the fulcrum guides are significantly bended, the yarns are strongly pressed onto the fulcrum guides and hence great forces are exerted from the yarns to the fulcrum guides. This causes the following problem.

[0005] For example, in a case of fixed fulcrum guides as described in Patent Literature 1 above, as the yarns run while being strongly pressed onto the fulcrum guides, the fulcrum guides tend to be worn.

[0006] In view of the above, an object of the present invention is to provide a yarn winder in which exertion of a significant force from a yarn to a fulcrum guide is avoided at the time of yarn threading.

[0007] A yarn winder of the present invention is a yarn winder for winding yarns onto bobbins attached to a bobbin holder, comprising guide units each of which includes: a cylindrical fulcrum guide which functions as a fulcrum when a yarn is wound onto a bobbin while being traversed; and a yarn deposit guide on which the yarn to be threaded to the fulcrum guide is deposited while being in contact with the fulcrum guide, when the yarn sucked and held by a sucking holding member configured to suck and retain the yarn is threaded to the fulcrum guide,

the yarn deposit guide being provided at a position satisfying an inequality (1) θ1<θ2,

where Θ1 is a bending angle between a first vector and a second vector viewed in an axial direction of the fulcrum guide when the yarn is deposited on the yarn deposit guide at the time of yarn threading to the fulcrum guide, the first vector is a vector in which the starting point is the center of the fulcrum guide and the termination point is a contact point on the upstream side in a yarn running direction between the outer circumferential surface of the fulcrum guide and the yarn, and the second vector is a vector in which the starting point is the center of the fulcrum guide and the termination point is a contact point on the downstream side in the yarn running direction between the outer circumferential surface of the fulcrum guide and the yarn, and

Θ2 is a virtual bending angle between a virtual first vector and a virtual second vector viewed in the axial direction of the fulcrum guide when the yarn is directly threaded to the fulcrum guide without being deposited on the yarn deposit guide at the time of yarn threading to the fulcrum guide, the virtual first vector is a vector in which the starting point is the center of the fulcrum guide and the termination point is a contact point on the upstream side in the yarn running direction between the outer circumferential surface of the fulcrum guide and the yarn, and the virtual second vector is a vector in which the starting point is the center of the fulcrum guide and the termination point is a contact point on the downstream side in the yarn running direction between the outer circumferential surface of the fulcrum guide and the yarn.

[0008] When the yarn is sucked and held by the sucking holding member in order to perform yarn threading to the fulcrum guide, the tension of the yarn is high as compared to a state in which the yarn is being wound. When the yarn that is greatly tensioned in this way is threaded to the fulcrum guide, if the yarn making contact with the fulcrum guide is significantly bended, the yarn is strongly pressed onto the fulcrum guide and hence a great force is exerted from the yarn to the fulcrum guide. In the arrangement of the present invention described above, when the yarn threading is performed, the bending angle Θ1 between the yarn and the fulcrum guide when the yarn is deposited on the yarn deposit guide is arranged to be smaller than the virtual bending angle Θ2 between the yarn Y and the fulcrum guide when the yarn is directly threaded to the fulcrum guide. Because the yarn is deposited on the yarn deposit guide at the time of the yarn threading, it is possible to avoid a significantly bended yarn from making contact with the fulcrum guide. On this account, it is possible to avoid a large force from being exerted from the yarn to the fulcrum guide at the time of the yarn threading.

[0009] The yarn winder of the present invention is a yarn winder for winding yarns onto bobbins attached to a bobbin holder, comprising guide units each of which includes: a cylindrical fulcrum guide which functions as a fulcrum when a yarn is wound onto a bobbin while being traversed; and a yarn deposit guide on which the yarn to be threaded to the fulcrum guide is deposited while not being in contact with the fulcrum guide, when the yarn sucked and held by a sucking holding member configured to suck and retain the yarn is threaded to the fulcrum guide.

[0010] When the yarn is sucked and held by the sucking holding member in order to perform yarn threading to the fulcrum guide, the tension of the yarn is high as compared to a state in which the yarn is being wound. When the yarn that is greatly tensioned in this way is threaded to the fulcrum guide, if the yarn making contact with the fulcrum guide is significantly bended, the yarn is strongly pressed onto the fulcrum guide and hence a great force is exerted from the yarn to the fulcrum guide. According to the above-described arrangement of the present invention, as the yarn is deposited on the yarn deposit guide at the time of yarn threading, the yarn does not make contact with the fulcrum guide. On this account, it is possible to avoid a large force from being exerted from the yarn to the fulcrum guide at the time of the yarn threading.

[0011] Preferably, the yarn winder of the present invention may further comprise a preventer which is provided at a position below the fulcrum guide and between the sucking holding member and the yarn deposit guide at the time of yarn threading to the fulcrum guide and is configured to prevent the yarn deposited on the yarn deposit guide from making contact with the fulcrum guide.

[0012] According to this arrangement of the present invention, even if the sucking holding member moves to a position above the yarn deposit guide after depositing the yarn on the yarn deposit guide, the yarn running between the sucking holding member and the yarn deposit guide makes contact with the preventer from below and is therefore prevented from moving to a position above the preventer. In this way, it is possible to further reliably prevent the yarn from making contact with the fulcrum guide at the time of yarn threading.

[0013] Preferably, in the yarn winder of the present invention, the fulcrum guide is rotatable about a central axis.

[0014] According to this arrangement of the present invention, it is possible to avoid a large force from being exerted from the yarn to the rotatable fulcrum guide at the time of the yarn threading. It is therefore possible to avoid the fulcrum guide from receiving a large torque from the yarn and rotating at a high speed at the time of the yarn threading, and to effectively suppress the advance of deterioration of the bearing structure of the fulcrum guide.

[0015]  Preferably, in the yarn winder of the present invention, the fulcrum guide is fixed.

[0016] According to this arrangement of the present invention, it is possible to avoid a large force from being exerted from the yarn to the fixed fulcrum guide at the time of the yarn threading. On this account, it is possible to avoid the yarn from being strongly pressed onto the fulcrum guide at the time of the yarn threading, and to effectively suppress the fulcrum guide from being significantly worn.

[0017] Preferably, in the yarn winder of the present invention, the yarn deposit guide is arranged so that the yarn is detached and threaded to the fulcrum guide in accordance with yarn threading to a component of the yarn winder, which is on the downstream side of the fulcrum guide in the yarn running direction.

[0018] According to this arrangement of the present invention, the yarn is detached from the yarn deposit guide in accordance with yarn threading to a component on the downstream side of the fulcrum guide. This makes it possible to do away with the operation to detach the yarn from the yarn deposit guide, and hence the yarn is easily handed over from the yarn deposit guide to the fulcrum guide.

[0019] Preferably, in the yarn winder of the present invention, the yarn deposit guide is arranged so that the yarn is detached when the yarn is threaded to a groove formed in the circumferential surface of the bobbin.

[0020] According to this arrangement of the present invention, the yarn is detached from the yarn deposit guide in accordance with the threading of the yarn into the groove formed in the circumferential surface of the bobbin. This makes it possible to do away with the operation to detach the yarn from the yarn deposit guide, and hence the yarn is easily handed over from the yarn deposit guide to the fulcrum guide.

[0021] Preferably, the yarn winder of the present invention is arranged such that a downstream member movable with the yarn being threaded to the downstream member is provided on the downstream side of the fulcrum guide in the yarn running direction, and the yarn deposit guide is arranged so that the yarn is detached in accordance with movement of the downstream member.

[0022] According to this arrangement of the present invention, the yarn is detached from the yarn deposit guide in accordance with the movement of the downstream member. This makes it possible to do away with the operation to detach the yarn from the yarn deposit guide, and hence the yarn is easily handed over from the yarn deposit guide to the fulcrum guide.

[0023] Preferably, in the yarn winder of the present invention, the yarn deposit guide includes a yarn deposit portion which extends in the axial direction of the fulcrum guide and on which the yarn is deposited.

[0024] With this arrangement of the present invention, the yarn can be easily deposited on the yarn deposit guide in such a way that the yarn is deposited along the yarn deposit portion extending in the axial direction.

[0025] Preferably, in the yarn winder of the present invention, the yarn deposit portion extends to reach an intermediate portion of the fulcrum guide in the axial direction.

[0026] With this arrangement of the present invention, the yarn detached from the end portion of the yarn deposit portion locates at an intermediate portion of the fulcrum guide in the axial direction. On this account, the yarn detached from the yarn deposit guide can be handed over to the fulcrum guide without being moved in the axial direction. On this account, the yarn detached from the yarn deposit guide can be easily handed over to the fulcrum guide.

[0027] Preferably, the yarn winder of the present invention is arranged such that the yarn deposit guide includes a drop prevention portion which extends in an intersecting direction intersecting with the axial direction and prevents the yarn from dropping off from the yarn deposit portion.

[0028] This arrangement of the present invention makes it possible by the drop prevention portion to avoid the yarn from unintentionally dropping off from the yarn deposit guide.

[0029] Preferably, in the yarn winder of the present invention, the guide units are aligned along a winding axis of the bobbin holder.

[0030] Such a yarn winder makes it possible to avoid the fulcrum guides onto which the yarns are strongly placed at the time of the yarn threading from receiving large forces from the yarns.

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] 

FIG. 1 is a side view of a spun yarn take-up apparatus of an embodiment.

FIG. 2 is a side view of guide units aligned in a front-rear direction.

FIG. 3 is a side view of a second guide unit.

FIG. 4 is a side view of the second guide unit when a yarn is directly threaded to a fulcrum guide in yarn threading.

FIG. 5 shows the second guide unit viewed from a direction V of FIG. 3.

FIG. 6(a) is a side view of a fulcrum guide in yarn winding. FIG. 6(b) is a table showing the relationship between a bending angle of a yarn threaded to a fulcrum guide in yarn winding and the number of rotations of the fulcrum guide.

FIG. 7 is a side view of a second guide unit of a second modification.

FIG. 8 is a side view of a second guide unit of a third modification.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] With reference to drawings, the following will describe an embodiment in which a yarn winder having a guide unit of the present invention is applied to a spun yarn take-up apparatus.

(Spun Yarn Take-Up Apparatus)

[0033] FIG. 1 is a profile of a spun yarn take-up apparatus 1 of the present embodiment. In this specification, forward, rearward, leftward, rightward, upward, and downward directions shown in FIG. 1 will be referred to as forward, rearward, leftward, rightward, upward, and downward directions of the spun yarn take-up apparatus 1.

[0034] The spun yarn take-up apparatus 1 is configured to take up plural (16 in this embodiment) yarns Y spun out from a spinning apparatus 2 and includes godet rollers 3 and 4 and a yarn winder 10. The spinning apparatus 2 is provided above the spun yarn take-up apparatus 1 and is configured to spin out yarns Y which are made of synthetic resin. The godet rollers 3 and 4 are provided below the spinning apparatus 2 and are rotationally driven by an unillustrated motor. The yarns Y spun out from the spinning apparatus 2 are sent to the yarn winder 10 via the godet rollers 3 and 4.

[0035] The yarn winder 10 is provided below the godet rollers 3 and 4. The yarn winder 10 includes two bobbin holders 13 cantilevered by a turret 12 accommodated in a frame 11. Each bobbin holder 13 extends in the front-rear direction. In other words, the winding axis direction of the bobbin holder 13 is identical with the front-rear direction. A rear end portion of each bobbin holder 13 is supported by a turret 12. It is possible to attach bobbins B to each bobbin holder 13 so that the bobbins B are aligned in the front-rear direction. In the circumferential surface of each bobbin B attached to each bobbin holder 13, a groove 50 is formed (see FIG. 1). To be more specific, a groove 50 in which a yarn can be threaded is formed in the vicinity of an end portion of the circumferential surface of each bobbin B. A yarn Y spun out from the spinning apparatus 2 is threaded into the groove 50 formed in the bobbin B, and then the yarn is wound onto the entire circumferential surface of the bobbin B as the yarn Y is traversed by a traverse device 17 (described later). The bobbin holders 13 are each rotationally driven about an axis by an unillustrated motor.

[0036] The turret 12 is a disc-shaped member having a rotational axis in parallel to the front-rear direction. The bobbin holders 13 are attached to an upper position and a lower position of the turret 12, respectively. The upper position and the lower position are deviated from each other in the circumferential direction by 180 degrees. As the turret 12 is rotated, the two bobbin holders 13 are moved between the upper and lower positions. At the bobbin holder 13 at the upper position, the yarns Y are wound onto the bobbins B and packages P are formed. Meanwhile, at the bobbin holder 13 at the lower position, the packages P are collected and new bobbins B are attached.

[0037] The yarn winder 10 includes a supporting frame 14 cantilevered by the frame 11. The supporting frame 14 is supported at its rear end portion by the frame 11. Guide units 15 are provided above the supporting frame 14. The guide units 15 that are identical in number with the yarns Y are aligned in the front-rear direction. In other words, in the present embodiment, 16 guide units 15 are aligned in the front-rear direction. In FIG. 2(a), some of the 16 guide units 15 are not shown. Each guide unit 15 includes a fulcrum guide 16. On the supporting frame 14, traverse devices 17 are provided to be aligned in the front-rear direction. The number of the traverse devices 17 is identical with the number of the yarns Y. The traverse device 17 is configured to traverse the yarn Y in the front-rear direction about the fulcrum guide 16 of the corresponding guide unit 15.

[0038] Below the supporting frame 14, a contact roller 18 rotatably supported by the supporting frame 14 is provided. The contact roller 18 makes contact with the outer circumferential surfaces of the packages P retained by the bobbin holder 13 at the upper position. As the contact roller 18 rotates while applying a predetermined contact pressure to each package P during yarn winding, the shape of the package P is adjusted.

(Guide Unit)

[0039] The structure of the guide units 15 will be described with reference to FIG. 2 to FIG. 5. FIG. 2 is a side view of the guide units 15 aligned in the front-rear direction. FIG. 2(a) shows a state in which the guide units15 are at separated positions, whereas FIG. 2(b) shows a state in which the guide units 15 are at gathered positions. The separated positions are positions of the guide units 15 when the yarns Y are wound onto the bobbins B. The gathered positions are positions of the guide units 15 when the yarns Y are threaded to the guide units 15. The guide units 15 at the gathered positions are close to each other. The guide units 15 at the separated positions are remote from each other as compared those at the gathered positions. The guide units 15 are arranged to be movable between the separated positions and the gathered positions. The guide units 15 at the gathered positions are on the front side in the front-rear direction on the whole, as compared to those at the separated positions. In the present embodiment, yarn threading to the guide units 15 is carried out from the front side of the yarn winder 10.

[0040] The guide units 15 are separated into first guide units 15a and second guide units 15b. The first guide units 15a are 12 guide units 15 on the front side among the 16 guide units 15. The second guide unit 15b are four guide units 15 on the rear side among the 16 guide units 15. Hereinafter, when guide units 15 are simply referred to, the guide units 15 will indicate both the first guide units 15a and the second guide units 15b. To begin with, arrangements shared between the first guide units 15a and the second guide units 15b will be described.

(Arrangement Shared between First Guide Units and Second Guide Units)

[0041] As shown in FIG. 2, each guide unit 15 includes a fulcrum guide 16 and a slider 21. The fulcrum guide 16 is a guide functioning as a fulcrum when a yarn Y is wound onto a bobbin B while being traversed by the traverse device 17. The fulcrum guide 16 is cylindrical in shape. The axial direction of the fulcrum guide 16 is identical with the left-right direction. The fulcrum guide 16 is arranged to be rotatable about the central axis. The fulcrum guide 16 receives a predetermined degree of rotational resistance. The yarn Y is placed on the outer circumferential surface of the fulcrum guide 16. When the yarn Y is wound, the running yarn Y is in contact with the outer circumferential surface of the fulcrum guide 16.

[0042] The slider 21 supports the fulcrum guide 16. The slider 21 is slidably attached to a guide rail 22 extending in the front-rear direction. To be more specific, the guide rail 22, the sliders 21 are attached to be lined up in the front-rear direction and to be slidable. Sliders 21 neighboring to each other are connected to each other by an unillustrated belt. The guide rail 22 is fixed to a supporting frame 14 by an unillustrated bracket. Each slider 21 is moved in the front-rear direction along the guide rail 22 by an air cylinder 23. With this arrangement, each guide unit 15 is moved between the separated position and the gathered position. The air cylinder 23 is provided on the rear side of the rearmost slider 21. For example, a rod 23a of the air cylinder 23 is connected to the rearmost slider 21. A driving device for moving the sliders 21 may be different from the air cylinder 23, and may be an actuator such as a motor.

[0043]  Yarn threading to the fulcrum guides 16 is performed, for example, in such a way that an operator operates a suction gun 60 (sucking holding member; see, e.g., FIG. 3) that sucks and holds yarns Y. When the yarns Y are sucked and held by the suction gun 60, the tension of the yarns Y is high as compared to a state in which the yarns Y are being wound. When yarn threading is performed for the fulcrum guides 16 of the yarn winder 10, the yarns Y threaded to the fulcrum guides 16 that are remote from a place where the operator operates the suction gun 60 (i.e., the front side of the yarn winder 10) are significantly bended. In the present embodiment, for example, the yarns Y threaded to the fulcrum guides 16 of the four guide units 15 on the rear side among the 16 guide units 15 are significantly bended. When the yarns Y that are greatly tensioned due to the sucking and holding by the suction gun 60 are threaded to the fulcrum guides 16, if the yarns Y making contact with the fulcrum guides 16 are significantly bended, the yarns Y are strongly pressed onto the fulcrum guides 16 and hence great forces are exerted from the yarns Y to the fulcrum guides 16. This causes the following problem.

[0044] In a case of rotational fulcrum guides 16 each rotatable about the central axis as in the present embodiment, each fulcrum guide 16 may receive a great force from the yarn Y and hence the fulcrum guide 16 may rotate rapidly. As a result, the bearing structure of the fulcrum guide 16 may not be durable to the high-speed rotation, and may be damaged.

[0045] For example, FIG. 6(b) shows a bending angle θ (degrees) between the fulcrum guide 16 of each of the four guide units 15 on the rear side among the 16 guide units 15 and the yarn Y threaded to that fulcrum guide 16 and the number of rotations (rpm) of the fulcrum guide 16, during yarn winding. The "ENDS" in FIG. 6(b) are the reference numbers of the fulcrum guides 16, which are counted as 1, 2, 3, and so on from the front side in the front-rear direction. Therefore 13 to 16 ends shown in FIG. 6(b) indicate the four fulcrum guides 16 on the rear side. The "bending angle θ" is a bending angle between a vector XQ and a vector XR when viewed in the left-right direction (the axial direction of the fulcrum guide 16) (see FIG. 6(a)). The sign "X" indicates the center of the fulcrum guide 16. The sign "Q" indicates a contact point on the upstream side in the yarn running direction between the yarn Y and the fulcrum guide 16 on the outer circumferential surface of the fulcrum guide 16 during yarn winding. The sign "R" indicates a contact point on the downstream side in the yarn running direction between the yarn Y and the fulcrum guide 16 on the outer circumferential surface of the fulcrum guide 16, when the yarn Y is deposited to a yarn deposit guide 31. The vector XQ is a vector in which the starting point is X and the termination point is Q. The vector XR is a vector in which the starting point is X and the termination point is R. As shown in FIG. 6(b), while the yarns are being wound, the closer the fulcrum guide 16 is to the rear side, the larger the bending angle θ is, i.e., the higher acceleratingly the number of rotations is. As described above, yarn threading to the guide units 15 is carried out from the front side of the yarn winder 10. On this account, at the time of the yarn threading to the fulcrum guide 16, the yarn Y is threaded to the fulcrum guide 16 and is then greatly pulled forward. On this account, at the time of the yarn threading to the fulcrum guide 16, the bending angle θ of the yarn Y threaded to the fulcrum guide 16 is obviously larger than the bending angle θ during the yarn winding. The closer the guide unit 15 is to the rear side, the higher the degree of increase of the bending angle θ at the time of the yarn threading is. Furthermore, the result shown in FIG. 6(b) indicates that, the larger the bending angle θ is, the larger the number of rotations of the fulcrum guide 16 is. Due to this, when the bending angle θ is further increased at the time of yarn threading, the fulcrum guide 16 receives a large force from the yarn Y and the fulcrum guide 16 rotates at a high speed. Consequently, the bearing structure of the fulcrum guide 16 may not be able to endure the high-speed rotation and may be damaged.

[0046] Under this circumstance, in order to avoid the exertion of a large force from the yarns Y to the fulcrum guides 16 of the guide units 15 on the rear side at the time of yarn threading, the inventors of the subject application keenly examined whether it was beneficial to provide a later-described yarn deposit guide 31. While in the present embodiment the four guide units 15 on the rear side among the 16 guide units 15 are the second guide units 15b, the disclosure is not limited to this arrangement.

(Second Guide Unit)

[0047] The following will describe the structure of the second guide units 15b each having the yarn deposit guide 31 with reference to FIG. 3 to FIG. 5. Four second guide units 15b are provided in the present embodiment, and the second guide units 15b are aligned in the front-rear direction (i.e., the winding axis direction of the bobbin holder 13). A second guide unit 15b having a yarn deposit guide 31 is equivalent to the guide unit of the present invention. The arrangements shared between the first guide units 15a and the second guide units 15b have been described above. FIG. 3 is a side view of the second guide unit 15b. FIG. 4 is a side view of the second guide unit when a yarn is directly threaded to a fulcrum guide in yarn threading. FIG. 5 is a side view showing the second guide unit viewed in a direction V of FIG. 3.

[0048] As shown in FIG. 3, the second guide unit 15b has a yarn deposit guide 31. On the yarn deposit guide 31, a yarn Y to be threaded to the fulcrum guide 16 is deposited when yarn threading to the fulcrum guide 16 is performed while the yarn Y is sucked and held by the suction gun 60. In the present embodiment, the yarn Y deposited on the yarn deposit guide 31 in the yarn threading is arranged to make contact with the circumferential surface of the fulcrum guide 16 at a position on the downstream side of the yarn deposit guide 31 in the yarn running direction. To be more specific, a yarn deposit portion 32 (described later) of the yarn deposit guide 31 is substantially directly behind the fulcrum guide. The yarn Y deposited on the yarn deposit guide 31 in the yarn threading makes contact with the circumferential surface of the fulcrum guide 16 at a position that is forward of and below the yarn deposit guide 31.

[0049] The yarn deposit guide 31 is arranged so that the yarn Y is detached and threaded to the fulcrum guide 16 in accordance with yarn threading to a component of the yarn winder 10, which is on the downstream side of the fulcrum guide 16 in the yarn running direction. To be more specific, the yarn deposit guide 31 is arranged so that the yarn Y is detached when the yarn Y is threaded to a groove 50 formed in the circumferential surface of a bobbin B that is a component on the downstream side of the fulcrum guide 16 in the yarn running direction.

[0050] In addition to the above, the yarn deposit guide 31 is provided at a position satisfying the following inequality (1).

[0051] As shown in FIG. 3, Θ1 is a bending angle between a first vector XA and a second vector XB viewed in the left-right direction (i.e., the axial direction of the fulcrum guide 16) when the yarn Y is deposited on the yarn deposit guide 31 at the time of yarn threading to the fulcrum guide 16. The sign "X" indicates the center of the fulcrum guide 16. The sign "A" indicates a contact point on the upstream side in the yarn running direction between the yarn Y and the fulcrum guide 16 on the outer circumferential surface of the fulcrum guide 16, when the yarn Y is deposited to a yarn deposit guide 31. The sign "B" indicates a contact point on the downstream side in the yarn running direction between the yarn Y and the fulcrum guide 16 on the outer circumferential surface of the fulcrum guide 16, when the yarn Y is deposited to a yarn deposit guide 31. The first vector XA is a vector in which the starting point is X and the termination point is A. The second vector XB is a vector in which the starting point is X and the termination point is B. A bending angle Θ1 when the yarn Y deposited on the yarn deposit guide 31 and the fulcrum guide 16 make contact with each other at a single point is 0 degree.

[0052] As shown in FIG. 4, Θ2 is a virtual bending angle between a virtual first vector XC and a virtual second vector XD viewed in the left-right direction (i.e., the axial direction of the fulcrum guide 16) when the yarn Y is directly threaded to the fulcrum guide 16 without being deposited on the yarn deposit guide 31 at the time of yarn threading to the fulcrum guide 16. The sign "C" indicates a contact point on the upstream side in the yarn running direction between the yarn Y and the fulcrum guide 16 on the outer circumferential surface of the fulcrum guide 16, when the yarn Y is directly threaded to the fulcrum guide 16 without being deposited to the yarn deposit guide 31. The sign "D" indicates a contact point on the downstream side in the yarn running direction between the yarn Y and the fulcrum guide 16 on the outer circumferential surface of the fulcrum guide 16, when the yarn Y is directly threaded to the fulcrum guide 16 without being deposited to the yarn deposit guide 31. The virtual first vector XC is a vector in which the starting point is X and the termination point is C. The virtual second vector XD is a vector in which the starting point is X and the termination point is D.

[0053] The yarn deposit guide 31 includes the yarn deposit portion 32 and a drop prevention portion 33. As shown in FIG. 5, the yarn deposit portion 32 is a portion where the yarn Y to be threaded to the fulcrum guide 16 is deposited at the time of yarn threading to the fulcrum guide 16. The yarn deposit portion 32 extends in the left-right direction (the axial direction of the fulcrum guide 16). To be more specific, the yarn deposit portion 32 extends to reach an intermediate portion of the fulcrum guide 16 in the left-right direction. To put it differently, the yarn deposit portion 32 extends to reach a position that is to the left of the right end portion and to the right of the left end portion of the fulcrum guide 16 in the left-right direction. The yarn deposit portion 32 is arranged so that the yarn Y is detached from its left end portion. When viewed in the left-right direction, the yarn deposit portion 32 is tilted so that the upper end is on the rear side of the lower end (see FIG. 3).

[0054] The drop prevention portion 33 is a portion for preventing the yarn Y from dropping off from the yarn deposit portion 32. As shown in FIG. 3 and FIG. 5, the drop prevention portion 33 extends in a direction orthogonal to the left-right direction (axial direction of the fulcrum guide 16). To be more specific, the drop prevention portion 33 extends downward from an end portion (i.e., the left end portion) of the yarn deposit portion 32 from which the yarn Y is detached. The drop prevention portion 33 is tilted so that the upper end is on the front side of the lower end (see FIG. 3). The drop off of the yarn Y deposited on the yarn deposit portion 32 is prevented in such a way that, when the yarn Y on the yarn deposit portion 32 moves toward the left end portion that is an end portion from which the yarn Y is detached, the yarn Y makes contact with the right side face of the drop prevention portion 33.

(Yarn Threading to Fulcrum Guide)

[0055] The following will describe steps when an operator performs yarn threading to the fulcrum guide 16 by using the suction gun 60. Steps in which the operator operates the suction gun 60 to place the yarns Y spun out from the spinning apparatus 2 onto the godet rollers 3 and 4 are not explained.

[0056] The operator operates the suction gun 60 to thread the yarns Y sent from the godet roller 4 to the fulcrum guides 16 of the respective guide units 15. In doing so, the operator operates the suction gun 60 to deposit, on the yarn deposit guide 31, the yarns Y that are to be threaded to the fulcrum guides 16 of the second guide units 15b (see FIG. 3) .

[0057] Subsequently, the operator operates the suction gun 60 to perform yarn threading to components of the fulcrum guide 16 on the downstream side. The components of the fulcrum guide 16 on the downstream side are, for example, traverse guides (not illustrated) provided in the traverse device 17, a separator (not illustrated), and a groove 50 formed in the circumferential surface of each bobbin B attached to the bobbin holder 13. The separator is a member provided to guide a yarn Y threaded to the traverse guide to a position where the yarn Y is wound onto each bobbin B attached to the bobbin holder 13. The separator is not detailed here.

[0058] As the yarn threading to the components on the downstream side of the fulcrum guide 16 advances and the yarn Y is threaded to the groove 50 formed in the circumferential surface of each bobbin B attached to the bobbin holder 13, the yarn Y deposited on the yarn deposit guide 31 is pulled leftward (see a full-line arrow in FIG. 5). As a result of this, the yarn Y climbs over the drop prevention portion 33 and is detached from the yarn deposit guide 31, and the yarn Y is directly threaded to the fulcrum guide 16. The yarn path of the yarn Y detached from the yarn deposit guide 31 and threaded to the fulcrum guide 16 is indicated by a dotted line in FIG. 5. In this way, the yarn threading to the fulcrum guide 16 is completed.

(Effects)

[0059] The yarn winder 10 of the present embodiment includes the second guide units 15b each having the cylindrical fulcrum guide 16 and the yarn deposit guide 31 on which the yarn Y to be threaded to the fulcrum guide 16 is deposited when the yarn Y sucked and held by the suction gun 60 is threaded to the fulcrum guide 16. The yarn deposit guide 31 is provided at a position satisfying the following inequality (1).

[0060] Θ1 is a bending angle between a first vector XA and a second vector XB viewed in the left-right direction (i.e., the axial direction of the fulcrum guide 16) when the yarn Y is deposited on the yarn deposit guide 31 at the time of yarn threading to the fulcrum guide 16. The first vector XA is a vector in which the starting point is the center X of the fulcrum guide 16 and the termination point is a contact point A on the upstream side in the yarn running direction between the outer circumferential surface of the fulcrum guide 16 and the yarn Y. The second vector XB is a vector in which the starting point is the center X of the fulcrum guide 16 and the termination point is a contact point B on the downstream side in the yarn running direction between the outer circumferential surface of the fulcrum guide 16 and the yarn Y.

[0061] Θ2 is a virtual bending angle between a virtual first vector XC and a virtual second vector XD viewed in the left-right direction (i.e., the axial direction of the fulcrum guide 16) when the yarn Y is directly threaded to the fulcrum guide 16 without being deposited on the yarn deposit guide 31 at the time of yarn threading to the fulcrum guide 16. The virtual first vector XC is a vector in which the starting point is the center X of the fulcrum guide 16 and the termination point is a contact point C on the upstream side in the yarn running direction between the outer circumferential surface of the fulcrum guide 16 and the yarn Y. The virtual second vector XD is a vector in which the starting point is the center X of the fulcrum guide 16 and the termination point is a contact point D on the downstream side in the yarn running direction between the outer circumferential surface of the fulcrum guide 16 and the yarn Y.

[0062] When the yarn Y is sucked and held by the suction gun 60 for yarn threading to the fulcrum guide 16, the tension of the yarn Y is high as compared to a state in which the yarn Y is being wound. When the yarn Y that is greatly tensioned in this way is threaded to the fulcrum guide 16, if the yarn Y making contact with the fulcrum guide 16 is significantly bended, the yarn Y is strongly pressed onto the fulcrum guide 16 and hence a great force is exerted from the yarn Y to the fulcrum guide 16. In the present embodiment, when the yarn threading is performed, the bending angle Θ1 between the yarn Y and the fulcrum guide 16 when the yarn Y is deposited on the yarn deposit guide 31 is arranged to be smaller than the virtual bending angle Θ2 between the yarn Y and the fulcrum guide 16 when the yarn Y is directly threaded to the fulcrum guide 16. Because the yarn Y is deposited on the yarn deposit guide 31 at the time of the yarn threading, it is possible to avoid a significantly bended yarn Y from making contact with the fulcrum guide 16. On this account, it is possible to avoid a large force from being exerted from the yarn Y to the fulcrum guide 16 at the time of the yarn threading.

[0063] In the yarn winder 10 of the present embodiment, the fulcrum guide 16 is rotatable about the central axis. On this account, it is possible to avoid a large force from being exerted from the yarn Y to the rotatable fulcrum guide 16 at the time of the yarn threading. It is therefore possible to avoid the fulcrum guide 16 from receiving a large torque from the yarn Y and rotating at a high speed at the time of the yarn threading, and to effectively suppress the advance of deterioration of the bearing structure of the fulcrum guide 16.

[0064] In the yarn winder 10 of the present embodiment, the yarn deposit guide 31 is arranged so that the yarn Y is detached and threaded to the fulcrum guide 16 in accordance with yarn threading to a component of the yarn winder 10, which is on the downstream side of the fulcrum guide 16 in the yarn running direction. This makes it possible to do away with the operation to detach the yarn Y from the yarn deposit guide 31, and hence the yarn Y is easily handed over from the yarn deposit guide 31 to the fulcrum guide 16.

[0065] In the yarn winder 10 of the present embodiment, the yarn deposit guide 31 is arranged such that the yarn Y is detached when the yarn Y is threaded to the groove 50 formed in the circumferential surface of the bobbin B. This makes it possible to do away with the operation to detach the yarn Y from the yarn deposit guide 31, and hence the yarn Y is easily handed over from the yarn deposit guide 31 to the fulcrum guide 16.

[0066] In the yarn winder 10 of the present embodiment, the yarn deposit guide 31 has the yarn deposit portion 32 which extends in the left-right direction (axial direction of the fulcrum guide 16) and on which the yarn Y is deposited. With this arrangement, the yarn Y can be easily deposited on the yarn deposit guide 31 in such a way that the yarn Y is deposited along the yarn deposit portion 32 extending in the left-right direction.

[0067] In the yarn winder 10 of the present embodiment, the yarn deposit portion 32 extends to reach an intermediate portion of the fulcrum guide 16 in the left-right direction (axial direction of the fulcrum guide 16). With this arrangement, the yarn Y detached from the end portion of the yarn deposit portion 32 locates at an intermediate portion of the fulcrum guide 16 in the left-right direction. On this account, the yarn Y detached from the yarn deposit guide 31 can be handed over to the fulcrum guide 16 without being moved in the left-right direction. On this account, the yarn Y detached from the yarn deposit guide 31 can be easily handed over to the fulcrum guide 16.

[0068] In the yarn winder 10 of the present embodiment, the yarn deposit guide 31 has the drop prevention portion 33 which extends in the direction orthogonal to the left-right direction (axial direction of the fulcrum guide 16) and prevents the yarn Y from dropping off from the yarn deposit portion 32. It is therefore possible by the drop prevention portion 33 to avoid the yarn Y from unintentionally dropping off from the yarn deposit guide 31.

[0069] In the yarn winder 10 of the present embodiment, plural (four in the present embodiment) second guide units 15b are aligned in the front-rear direction (winding axis direction of the bobbin holder 13) . Such a yarn winder 10 makes it possible to avoid the fulcrum guides 16 onto which the yarns Y are strongly placed at the time of the yarn threading from receiving large forces from the yarns Y.

(Modifications)

[0070] 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.

(First Modification)

[0071] In the embodiment above, the fulcrum guide 16 is rotatable about the central axis. Alternatively, the fulcrum guide 16 may be fixed. In this case, it is possible to avoid a large force from being exerted from the yarn Y to the fixed fulcrum guide 16 at the time of the yarn threading. On this account, it is possible to avoid the yarn Y from being strongly pressed onto the fulcrum guide 16 at the time of the yarn threading, and to effectively suppress the fulcrum guide 16 from being significantly worn.

(Second Modification)

[0072] In the embodiment above, the yarn Y deposited on the yarn deposit guide 31 in the yarn threading is arranged to make contact with the circumferential surface of the fulcrum guide 16 at a position on the downstream side of the yarn deposit guide 31 in the yarn running direction (see FIG. 3). Alternatively, as shown in FIG. 7, the yarn Y deposited on the yarn deposit guide 31 at the time of yarn threading may be arranged to make contact with the circumferential surface of the fulcrum guide 16 at a position on the upstream side of the yarn deposit guide 31 in the yarn running direction. To be more specific, the yarn deposit portion 32 of the yarn deposit guide 31 is provided below and behind the fulcrum guide, and the yarn Y deposited on the yarn deposit guide 31 in the yarn threading makes contact with the circumferential surface of the fulcrum guide 16 at a position that is forward of and above the yarn deposit guide 31. Also in this case, the yarn deposit guide 31 is provided at a position satisfying the following inequality (1).

[0073] The definitions of Θ1 and Θ2 are identical with those in the embodiment above.

(Third Modification)

[0074] In the embodiment above and the second modification, the yarn Y deposited on the yarn deposit guide 31 in the yarn threading is arranged to make contact with the circumferential surface of the fulcrum guide 16 at a position on the upstream side or the downstream side of the yarn deposit guide 31 in the yarn running direction. Alternatively, as shown in FIG. 8, a yarn Y deposited on a yarn deposit guide 131 at the time of yarn threading may not make contact with the a fulcrum guide 16. To be more specific, the yarn deposit guide 131 is a guide on which the yarn Y to be threaded to the fulcrum guide 16 is deposited without making contact with the fulcrum guide 16 when the yarn Y sucked and held by the suction gun 60 is threaded to the fulcrum guide 16. The yarn deposit guide 131 of the third modification results in the following effects. As the yarn Y is deposited on the yarn deposit guide 131 at the time of yarn threading, the yarn Y does not make contact with the fulcrum guide 16. On this account, it is possible to avoid a large force from being exerted from the yarn Y to the fulcrum guide 16 at the time of the yarn threading.

[0075] In addition to the above, in the third modification, as shown in FIG. 8, a preventer 35 is provided to prevent the yarn Y deposited on the yarn deposit guide 131 from making contact with the fulcrum guide 16. The preventer 35 is provided at a position that is below the fulcrum guide 16 and between the suction gun 60 and the yarn deposit guide 131 when yarn threading to the fulcrum guide 16 is performed. To be more specific, the preventer 35 is provided forward of and below the yarn deposit guide 131 and the fulcrum guide 16 (see FIG. 8). The presence of the preventer 35 results in the following effects. Even if the suction gun 60 moves to a position above a yarn deposit portion (not illustrated in FIG. 8) of the yarn deposit guide 131 after depositing the yarn Y on the yarn deposit guide 131, the yarn Y running between the suction gun 60 and the yarn deposit guide 131 makes contact with the preventer 35 from below and is therefore prevented from moving to a position above the preventer 35. In this way, it is possible to further reliably prevent the yarn Y from making contact with the fulcrum guide 16 at the time of yarn threading.

(Fourth Modification)

[0076] In the embodiment above, the yarn deposit guide 31 is arranged such that the yarn Y is detached when the yarn Y is threaded to the groove 50 formed in the circumferential surface of the bobbin B. Alternatively, the yarn deposit guide 31 may be arranged so that the yarn is detached in accordance with the movement of a downstream member provided on the downstream side of the fulcrum guide 16 in the yarn running direction moves. The downstream member is a member which is movable with the yarn Y being threaded thereto. To be more specific, examples of the downstream member are traverse guides (not illustrated) provided in the traverse device 17 and a separator (not illustrated). The separator is a member provided to guide a yarn Y threaded to the traverse guide to a position where the yarn Y is wound onto each bobbin B attached to the bobbin holder 13. In the present invention, yarn threading to components on the downstream side in the yarn running direction of the fulcrum guide encompasses the above-described movement of the downstream member with the yarn Y being threaded thereto.

(Other Modifications)

[0077] In the embodiment above, 12 guide units 15 on the front side among 16 guide units 15 are first guide units 15a, whereas four guide units 15 on the rear side are second guide units 15b. Alternatively, for example, eight guide units 15 on the front side among 16 guide units 15 may be first guide units 15a, whereas eight guide units 15 on the rear side may be second guide units 15b. All guide units 15 may be second guide units 15b.

[0078] In the embodiment above, the yarn deposit portion 32 extends to reach an intermediate portion of the fulcrum guide 16 in the left-right direction (axial direction of the fulcrum guide 16). Alternatively, the yarn deposit portion 32 may extend beyond the fulcrum guide 16 in the left-right direction. To be more specific, the yarn deposit portion 32 may extend to reach a position that is to the left of the left end portion of the fulcrum guide 16 in the left-right direction.

[0079] In the embodiment above, the drop prevention portion 33 extends in a direction orthogonal to the left-right direction (axial direction of the fulcrum guide 16). Alternatively, the drop prevention portion 33 may extend in an intersecting direction which is not orthogonal to the left-right direction (axial direction of the fulcrum guide 16). The drop prevention portion 33 may not be provided.

[0080] In the embodiment above, one yarn deposit guide 31 is provided for one second guide unit 15b. Alternatively, two or more yarn deposit guides 31 may be provided for one second guide unit 15b.

[0081] In the embodiment above, the yarn deposit guide 31 is arranged so that the yarn Y is detached when the yarn Y is threaded to the groove 50 formed in the circumferential surface of a bobbin B that is a component on the downstream side of the fulcrum guide 16 in the yarn running direction in the yarn winder 10 and then the yarn Y is threaded to the fulcrum guide 16. In this regard, the yarn deposit guide 31 may be arranged differently. For example, the yarn deposit guide 31 may be arranged such that the yarn Y is detached by an operation of the suction gun 60 by the operator.

[0082] In the embodiment above, the suction gun 60 is operated by the operator. Alternatively, the suction gun 60 may be automatically operated by, for example, a robotic arm.

[0083] The preventer 35 is provided in the third modification described above. In this connection, the preventer 35 may be provided in each of the embodiment above, the first modification, and the second modification. This brings about the following effects. Even if the suction gun 60 moves to a position above the yarn deposit portion 32 of the yarn deposit guide 31 after depositing the yarn Y on the yarn deposit guide 31, the yarn Y running between the suction gun 60 and the yarn deposit guide 31 makes contact with the preventer 35 from below and is therefore prevented from moving to a position above the preventer 35. This further makes it possible to suppress increase in the bending angle Θ1 (defined above) in the yarn threading, with the result that application of a large force from the fulcrum guide 16 to the yarn Y is further suppressed.

[0084] The present invention is applicable to not only the spun yarn take-up apparatus 1 but also various yarn winders each of which is arranged to wind yarns Y.

Claims

1. A yarn winder (10) for winding yarns (Y) onto bobbins (B) attached to a bobbin holder (13), comprising guide units (15b) each of which includes:

a cylindrical fulcrum guide (16) which functions as a fulcrum when a yarn (Y) is wound onto a bobbin (B) while being traversed; and

a yarn deposit guide (31) on which the yarn (Y) to be threaded to the fulcrum guide (16) is deposited while being in contact with the fulcrum guide (16), when the yarn (Y) sucked and held by a sucking holding member (60) configured to suck and retain the yarn (Y) is threaded to the fulcrum guide (16),

the yarn deposit guide (31) being provided at a position satisfying an inequality (1) θ1<θ2,

where Θ1 is a bending angle between a first vector (XA) and a second vector (XB) viewed in an axial direction of the fulcrum guide (16) when the yarn (Y) is deposited on the yarn deposit guide (31) at the time of yarn threading to the fulcrum guide (16), the first vector (XA) is a vector in which the starting point is the center (X) of the fulcrum guide (16) and the termination point is a contact point (A) on the upstream side in a yarn running direction between the outer circumferential surface of the fulcrum guide (16) and the yarn (Y), and the second vector (XB) is a vector in which the starting point is the center (X) of the fulcrum guide (16) and the termination point is a contact point (B) on the downstream side in the yarn running direction between the outer circumferential surface of the fulcrum guide (16) and the yarn (Y), and

Θ2 is a virtual bending angle between a virtual first vector (XC) and a virtual second vector (XD) viewed in the axial direction of the fulcrum guide (16) when the yarn (Y) is directly threaded to the fulcrum guide (16) without being deposited on the yarn deposit guide (31) at the time of yarn threading to the fulcrum guide (16), the virtual first vector (XC) is a vector in which the starting point is the center (X) of the fulcrum guide (16) and the termination point is a contact point (A) on the upstream side in the yarn running direction between the outer circumferential surface of the fulcrum guide (16) and the yarn (Y), and the virtual second vector (XD) is a vector in which the starting point is the center (X) of the fulcrum guide (16) and the termination point is a contact point (B) on the downstream side in the yarn running direction between the outer circumferential surface of the fulcrum guide (16) and the yarn (Y).

2. A yarn winder (10) for winding yarns (Y) onto bobbins (B) attached to a bobbin holder (13), comprising guide units (15b) each of which includes:

a cylindrical fulcrum guide (16) which functions as a fulcrum when a yarn (Y) is wound onto a bobbin (B) while being traversed; and

a yarn deposit guide (31) on which the yarn (Y) to be threaded to the fulcrum guide (16) is deposited while not being in contact with the fulcrum guide (16), when the yarn (Y) sucked and held by a sucking holding member (60) configured to suck and retain the yarn (Y) is threaded to the fulcrum guide (16).

3. The yarn winder (10) according to claim 2, further comprising a preventer (35) which is provided at a position below the fulcrum guide (16) and between the sucking holding member (60) and the yarn deposit guide (31) at the time of yarn threading to the fulcrum guide (16) and is configured to prevent the yarn (Y) deposited on the yarn deposit guide (31) from making contact with the fulcrum guide (16).

4. The yarn winder (10) according to any one of claims 1 to 3, wherein, the fulcrum guide (16) is rotatable about a central axis.

5. The yarn winder (10) according to any one of claims 1 to 3, wherein, the fulcrum guide (16) is fixed.

6. The yarn winder (10) according to any one of claims 1 to 5, wherein, the yarn deposit guide (31) is arranged so that the yarn (Y) is detached and threaded to the fulcrum guide (16) in accordance with yarn threading to a component of the yarn winder (10), which is on the downstream side of the fulcrum guide (16) in the yarn running direction.

7. The yarn winder (10) according to claim 6, wherein, the yarn deposit guide (31) is arranged so that the yarn (Y) is detached when the yarn (Y) is threaded to a groove (50) formed in the circumferential surface of the bobbin (B).

8. The yarn winder (10) according to claim 6, wherein,

a downstream member movable with the yarn (Y) being threaded to the downstream member is provided on the downstream side of the fulcrum guide (16) in the yarn running direction, and

the yarn deposit guide (31) is arranged so that the yarn (Y) is detached in accordance with movement of the downstream member.

9. The yarn winder (10) according to any one of claims 1 to 8, wherein, the yarn deposit guide (31) includes a yarn deposit portion (32) which extends in the axial direction of the fulcrum guide (16) and on which the yarn (Y) is deposited.

10. The yarn winder (10) according to claim 9, wherein, the yarn deposit portion (32) extends to reach an intermediate portion of the fulcrum guide (16) in the axial direction.

11. The yarn winder (10) according to claim 9 or 10, wherein, the yarn deposit guide (31) includes a drop prevention portion (33) which extends in an intersecting direction intersecting with the axial direction and prevents the yarn (Y) from dropping off from the yarn deposit portion (32) .

12. The yarn winder (10) according to any one of claims 1 to 11, wherein, the guide units (15b) are aligned along a winding axis of the bobbin holder (13).

Drawing