Core yarn supply device, air spinning machine, and core yarn spinning method and package

Abstract

To provide a core yarn supply device, an air spinning machine, and a core yarn spinning method capable of properly supplying a core yarn even when a core yarn having elasticity is used.SOLUTION: A core yarn supply device 200 comprises: a core yarn bobbin holding part 50 for holding a core yarn bobbin CB wound with a core yarn C; a core yarn delivery part 100 for delivering the core yarn C; a slack securing part 80 which is provided between the core yarn bobbin holding part 50 and the core yarn delivery part 100 in the running direction of the core yarn C and ensures the slack of the core yarn C; and a clamp device 110 which is provided between the core yarn bobbin holding part 50 and the slack securing part 80 in the running direction of the core yarn C and prevents the slack securing part of the core yarn C whose slack has been secured by the slack securing part 80 from returning to the direction opposite to the running direction.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a core yarn supplying device, an air spinning machine, a core yarn spinning method, and a package. [Background technology]

[0002] There is known a spinning machine in which a core yarn is supplied to a draft device by a core yarn supplying device, and a yarn is produced by an air spinning device using the core yarn as a core (see, for example, Patent Document 1). This spinning machine has a core yarn let-off unit that lets out the core yarn, and a slack imparting section that imparts slack to the core yarn. When the spinning machine detects a yarn defect or detects the absence of a yarn (core yarn or spun yarn), the supply of the core yarn is interrupted, and the core yarn downstream of the core yarn let-off unit is cut. The slack imparting section is switched to a slack imparting state, and slack is imparted to the core yarn. This allows the core yarn to be reliably sent to the draft device by the action of air when the supply of the core yarn is resumed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-102268 A Summary of the Invention [Problem to be solved by the invention]

[0004] In some cases, a core yarn having elasticity is used in a core yarn supplying device. In the above-mentioned conventional core yarn supplying device, the slack is imparted to the core yarn by the slack imparting unit, but when the core yarn is sent out, the elastic core yarn tends to shrink in the direction opposite to the sending direction. In such a case, the core yarn may not be sent out properly to the drafting device.

[0005] An object of the present invention is to provide a core yarn supplying device, an air spinning machine, and a core yarn spinning method that are capable of properly feeding out a core yarn even when a stretchable core yarn is used. [Means for solving the problem]

[0006] A core yarn supplying device according to one embodiment of the present invention includes a core yarn bobbin holding section that holds a core yarn bobbin around which a core yarn is wound, a core yarn feeding section that feeds out the core yarn, a slack ensuring section that is provided between the core yarn bobbin holding section and the core yarn feeding section in the running direction of the core yarn and ensures slack in the core yarn, and a return prevention section that is provided between the core yarn bobbin holding section and the slack ensuring section in the running direction and prevents the slack ensured portion of the core yarn, the slack of which is ensured by the slack ensuring section, from returning in the opposite direction to the running direction.

[0007] According to this core yarn supplying device, the return prevention section provided at a position upstream of the slack ensuring section in the core yarn running direction prevents the slack ensuring section of the core yarn from returning upstream. Therefore, even when a stretchable core yarn is used, the core yarn can be properly fed out by the core yarn feed section. This allows the core yarn to be properly fed out.

[0008] The return prevention unit can be switched between a return prevention state in which the slack ensuring portion of the core yarn is prevented from returning and an open state in which the slack ensuring portion of the core yarn is free, and the return prevention unit may be switched from the return prevention state to the open state at the start of or immediately after the start of sending out the core yarn by the core yarn sending out unit. In this case, it is possible to reliably prevent the slack ensuring portion of the core yarn from returning upstream when the core yarn is sent out.

[0009] The return prevention portion may be a clamping device that clamps the core yarn. In this case, the clamping device physically clamps the core yarn, thereby preventing the core yarn from shifting upstream.

[0010] The core yarn supplying device may further include a tension applying unit that is provided between the core yarn bobbin holding unit and the core yarn letting-off unit in the traveling direction and applies tension to the core yarn while the core yarn is being supplied. In this case, the core yarn is preferably let out by the core yarn letting-off unit.

[0011] The clamping device may be disposed between the tension applying portion and the slack ensuring portion in the running direction. With this layout, the distance between the slack ensuring portion and the clamping device is shortened, and the propagation of the shrinkage of the core yarn is reduced. As a result, the reduction in the amount of slack can be avoided.

[0012] The tension applying unit may function as a return prevention unit by applying tension to the core yarn while the supply of the core yarn is stopped. In this case, the tension applying unit applies tension to the core yarn while the supply of the core yarn is stopped, and prevents the slack ensuring portion from returning while the supply of the core yarn is stopped. Since the tension applying unit has two functions, there is no need to install a separate clamp device.

[0013] The core yarn supplying device may further include a base portion supporting the slack ensuring unit. At least one thread path guide is fixed to the base portion to guide the core yarn so that the core yarn travels along a straight normal thread path while the core yarn is being supplied, and the slack ensuring unit is movably attached to the base portion and has an arm having two core yarn passing portions formed therein and a drive unit for moving the arm, such that when the arm is placed in the normal position, the thread path guide and the two core yarn passing portions are positioned on the normal thread path, and when the arm is placed in the slack ensuring position, the core yarn is guided while being bent at least four times. In this case, by bending the core yarn into an M shape, a large slack can be ensured in a small space.

[0014] The slack ensuring section may be provided with an adjustment section capable of adjusting the path length of the slack ensuring section of the core yarn. By adjusting the path length of the slack ensuring section in accordance with the elasticity of the core yarn, the core yarn can be appropriately sent to the draft device regardless of the type of core yarn.

[0015] The core yarn let-off section may change the let-off force according to the path length of the portion where slack is ensured for the core yarn. By changing the let-off force according to the elasticity of the core yarn, the core yarn can be appropriately supplied to the draft device regardless of the type of the core yarn.

[0016] As another aspect of the present invention, an air spinning machine may be provided that includes any one of the core yarn supplying devices described above, a drafting device that drafts a fiber bundle, an air jet spinning device that produces a yarn containing the core yarn by spinning the fiber bundle drafted by the drafting device using the core yarn supplied from the core yarn supplying device as a core, and a winding device that winds the yarn into a package. In this air spinning machine, the core yarn sending-out section of the core yarn supplying device is provided so as to face a position between the middle roller pair and the front roller pair of the drafting device. With this air spinning machine, the core yarn can be appropriately supplied to the drafting device by the above-mentioned action. A yarn containing a core yarn having elasticity can be appropriately produced to form a package.

[0017] In the air spinning machine, the length of the slack ensuring portion of the core yarn formed by the slack ensuring unit may be from one to three times the distance from the clamp unit in the core yarn let-off unit to the top roller of the front roller pair. In this case, the core yarn let-off by the core yarn let-off unit reliably reaches the front roller pair.

[0018] As yet another aspect of the present invention, there may be provided a core yarn spinning method for an air spinning machine including a core yarn supplying device including a core yarn bobbin holding section that holds a core yarn bobbin around which a core yarn is wound, a core yarn let-off section that lets off the core yarn, a slack ensuring section that is provided between the core yarn bobbin holding section and the core yarn let-off section in the running direction of the core yarn and ensures slack in the core yarn, and a return prevention section that is provided between the core yarn bobbin holding section and the slack ensuring section in the running direction and prevents the slack ensured portion of the core yarn whose slack has been ensured by the slack ensuring section from returning in the opposite direction to the running direction, a drafting device that drafts a fiber bundle, and an air jet spinning device that produces a yarn containing the core yarn by spinning the fiber bundle drafted by the drafting device using the core yarn supplied from the core yarn supplying device as a core. In the core yarn spinning method, an elastic core yarn is let out from the core yarn let-off section that is provided to face a position between a pair of middle rollers and a pair of front rollers of the drafting device, and a yarn containing the core yarn is produced by the air jet spinning device. This core yarn spinning method also allows the core yarn to be properly supplied to the drafting device due to the above-mentioned action, and allows a yarn containing a stretchable core yarn to be suitably produced to form a package.

[0019] In yet another aspect of the present invention, a package may be provided that is wound with a yarn containing an elastic core yarn produced by air jet spinning, the package having a plurality of seams in the yarn that are spaced apart from one another longer than the intervals between periodic seams resulting from bob replacement, and the yarn has no seams resulting from core replacement. A preferred package having a small number of seams is provided. Effect of the Invention

[0020] According to the present invention, even when a core yarn having elasticity is used, the core yarn can be appropriately supplied. [Brief description of the drawings]

[0021] [Figure 1] FIG. 1 is a front view of a spinning machine according to one embodiment of the present invention. [Diagram 2] FIG. 2 is a side view of a spinning unit of the spinning machine of FIG. [Diagram 3] FIG. 3 is a perspective view of a core yarn supplying unit of the spinning unit of FIG. [Figure 4] FIG. 4 is an enlarged view of the slack ensuring portion and the clamp device. [Diagram 5] FIG. 5 is a block diagram of each part that operates by air. [Figure 6] FIG. 6 is a diagram showing an example of a state in which the slack ensuring portion is placed at the slack ensuring position. [Figure 7] FIG. 7 is an enlarged view of the slack ensuring portion and the clamp device in the state shown in FIG. [Figure 8] FIG. 8 is a diagram showing another example of a state in which the slack ensuring portion is disposed at the slack ensuring position. [Figure 9] FIG. 9(a) is a diagram showing the distance between seams in a package according to one embodiment of the present invention, and FIG. 9(a) is a diagram showing the distance between seams in a package according to a reference embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In each drawing, the same or corresponding parts are denoted by the same reference numerals, and duplicated explanations will be omitted.

[0023] As shown in FIG. 1, a spinning machine 1 (air spinning machine) includes a plurality of spinning units 2, a yarn splicing cart 3, a doffing cart (not shown), a first end frame 4, and a second end frame 5. The plurality of spinning units 2 are arranged in a row. Each spinning unit 2 produces a yarn Y and winds it into a package P. When the yarn Y is cut in a certain spinning unit 2 or the yarn Y is broken for some reason, the yarn splicing cart 3 performs a yarn splicing operation on the spinning unit 2. When the package P in a certain spinning unit 2 becomes full, the doffing cart doffs the package P and supplies a new bobbin B to the spinning unit 2. The first end frame 4 houses a collection device that collects fiber waste, lint, and the like generated in the spinning units 2.

[0024] The second end frame 5 houses an air supply unit that adjusts the pressure of compressed air (air) supplied to the spinning machine 1 and supplies air to each part of the spinning machine 1, a drive motor for supplying power to each part of the spinning unit 2, etc. The second end frame 5 is provided with a machine control device 41, a display screen 42, and input keys 43. The machine control device 41 centrally manages and controls each part of the spinning machine 1. The display screen 42 can display information on the setting contents and status of the spinning unit 2, etc. The operator can perform setting work for the spinning unit 2 by performing appropriate operations using the input keys 43.

[0025] In the following description, in the travel paths of the sliver S, fiber bundle F (see FIG. 2), and yarn Y, the side where the sliver S is supplied is referred to as the upstream side, and the side where the yarn Y is wound is referred to as the downstream side. The side where the yarn Y travels relative to the spinning unit 2 is referred to as the front side. In this embodiment, a work passage (not shown) extending in the arrangement direction of the multiple spinning units 2 is provided in front of the spinning machine 1. An operator can operate and monitor each spinning unit 2 from the work passage.

[0026] 1 and 2, each spinning unit 2 includes, in order from upstream in the running direction of the yarn Y, a draft device 6, a core yarn supplying device 200, an air spinning device 7, a yarn monitoring device 8, a tension sensor 9, a yarn storage device 11, a waxing device 12, and a winding device 13. A unit controller 10 is provided for each of a predetermined number of spinning units 2, and controls the operation of the spinning units 2.

[0027] The draft device 6 drafts the sliver (fiber bundle) S. The draft device 6 has, in order from upstream in the running direction of the sliver S, a back roller pair 14, a third roller pair 15, a middle roller pair 16, and a front roller pair 17. Each of the roller pairs 14, 15, 16, and 17 has a bottom roller and a top roller. The bottom roller is rotated by a drive motor provided on the second end frame 5 or a drive motor provided on each spinning unit 2. An apron belt 18a is provided for the bottom roller of the middle roller pair 16. An apron belt 18b is provided for the top roller of the middle roller pair 16.

[0028] The core yarn supplying device 200 unwinds the core yarn C from the core yarn package CP and supplies the core yarn C to the air spinning device 7. Specifically, the core yarn supplying device 200 supplies the core yarn C from between the middle roller pair 16 and the front roller pair 17 of the draft device 6 onto the traveling path of the fiber bundle F. In this way, the core yarn supplying device 200 supplies the core yarn C to the air spinning device 7.

[0029] The air spinning device 7 uses the core yarn C supplied from the core yarn supplying device 200 as a core to twist the fiber bundle F drafted in the drafting device 6 with a swirling air flow to generate a yarn Y. In more detail (not shown), the air spinning device 7 has a spinning chamber, a fiber guide, a swirling air flow generating nozzle, and a hollow guide shaft. The fiber guide guides the core yarn C supplied from the core yarn supplying device 200 arranged upstream and the fiber bundle F supplied from the drafting device 6 into the spinning chamber. The swirling air flow generating nozzle is arranged around the path along which the core yarn C and the fiber bundle F travel. A swirling air flow is generated in the spinning chamber by air being sprayed from the swirling air flow generating nozzle. The swirling air flow causes each fiber end of the multiple fibers constituting the fiber bundle F to be inverted and swirled. The hollow guide shaft guides the yarn Y from the spinning chamber to the outside of the air spinning device 7.

[0030] The yarn monitoring device 8 monitors information on the traveling yarn Y between the air spinning device 7 and the yarn pooling device 11, and detects the presence or absence of a yarn defect based on the monitored information. When the yarn monitoring device 8 detects a yarn defect, it transmits a yarn defect detection signal to the unit controller 10. The yarn monitoring device 8 detects, for example, an abnormality in the thickness of the yarn Y and / or a foreign object contained in the yarn Y as a yarn defect. The yarn monitoring device 8 also detects yarn breakage (the presence or absence of the yarn Y), etc. The tension sensor 9 measures the tension of the traveling yarn Y between the air spinning device 7 and the yarn pooling device 11, and transmits a tension measurement signal to the unit controller 10. When the unit controller 10 determines that an abnormality exists based on the detection results of the yarn monitoring device 8 and / or the tension sensor 9, the yarn Y is cut in the spinning unit 2. Specifically, the supply of air to the air spinning device 7 is stopped, and the production of the yarn Y is interrupted, thereby cutting the yarn Y. Alternatively, the yarn Y may be cut by a cutter provided separately.

[0031] The waxing device 12 applies wax to the yarn Y between the yarn storage device 11 and the winding device 13.

[0032] The yarn pooling device 11 pools the yarn Y between the air spinning device 7 and the winding device 13. The yarn pooling device 11 has a yarn pooling roller that pools the yarn Y by winding the yarn Y around its outer circumferential surface. The yarn pooling device 11 has the following functions: stably drawing out the yarn Y from the air spinning device 7; preventing the yarn Y from slackening by pooling the yarn Y sent out from the air spinning device 7 during a yarn splicing operation by the yarn splicing cart 3, and the like; and preventing fluctuations in the tension of the yarn Y downstream of the yarn pooling device 11 from being transmitted to the air spinning device 7.

[0033] The winding device 13 winds the yarn Y generated by the air spinning device 7 onto a bobbin B to form a package P. The winding device 13 has a cradle arm 21, a winding drum 22, and a traverse guide 23. The cradle arm 21 rotatably supports the bobbin B. The cradle arm 21 is supported by a support shaft 24 so as to be able to swing, and brings the surface of the bobbin B or the surface of the package P into contact with the surface of the winding drum 22 with an appropriate pressure. A drive motor (not shown) provided on the second end frame 5 drives the winding drums 22 of the multiple spinning units 2 simultaneously. As a result, the bobbin B or the package P is rotated in the winding direction in each spinning unit 2. The traverse guide 23 of each spinning unit 2 is provided on a shaft 25 shared by the multiple spinning units 2. The drive motor of the second end frame 5 reciprocates the shaft 25 in the axial direction of the winding drum 22, causing the traverse guide 23 to traverse the yarn Y over a predetermined width relative to the rotating bobbin B or package P.

[0034] When the yarn Y is cut in a spinning unit 2 or broken for some reason, the yarn splicing cart 3 travels to the spinning unit 2 and performs a yarn splicing operation. The yarn splicing cart 3 has a yarn splicing device 26, a suction pipe 27, and a suction mouth 28. The suction pipe 27 is rotatably supported by a support shaft 31, and captures the yarn Y from the air spinning device 7 and guides it to the yarn splicing device 26. The suction mouth 28 is rotatably supported by a support shaft 32, and captures the yarn Y from the winding device 13 and guides it to the yarn splicing device 26. The yarn splicing device 26 splices the guided yarns Y together. The yarn splicing device 26 is a splicer that uses compressed air, a knotter that mechanically splices the yarn Y, or the like.

[0035] When the yarn splicing cart 3 performs a yarn splicing operation, it rotates the package P in the counter-winding direction (reverse rotation). At this time, the cradle arm 21 is moved by an air cylinder (not shown) so that the package P is separated from the winding drum 22, and the package P is reversely rotated by a reverse rotation roller (not shown) provided on the yarn splicing cart 3.

[0036] A more detailed description will be given of the above-mentioned core yarn supplying device 200. As shown in FIG.

[0037] The core yarn bobbin holding section 50 holds a core yarn package CP formed by winding a core yarn C around a core yarn bobbin CB. The core yarn bobbin holding section 50 supports the core yarn package CP at a position upstream of the core yarn supplying unit 51 in the running direction of the core yarn C (hereinafter referred to as the core yarn running direction). The core yarn supplying unit 51 supplies the core yarn C while applying tension to the core yarn C that is unwound from the core yarn package CP and guided via a guide roller 53. The core yarn guiding section 52 guides the core yarn C supplied from the core yarn supplying unit 51 between the middle roller pair 18 and the front roller pair 19 of the draft device 6.

[0038] The core yarn supplying device 200 of the present embodiment is capable of supplying an elastic core yarn C. However, the core yarn supplying device 200 may be capable of supplying other types of core yarn C (for example, a monofilament-based core yarn, a multifilament core yarn).

[0039] The elastic core yarn C may be composed of two types of polymers (so-called dual core yarn) or one type of polymer (so-called single core yarn). As an example of a dual core yarn, the core yarn C may be a yarn composed of polyurethane (PU) and polyester filament (T400; manufactured by Toray Opelontex Co., Ltd.). The elasticity of the core yarn C means, for example, that it exhibits a value of elastic extension rate of 50% or more in the elasticity measurement according to JIS L 1013.

[0040] 3, the core yarn supplying unit 51 includes a unit base 60 (base portion), a core yarn detection device 90, a tension applying portion 70, a slack ensuring portion 80, and a core yarn letting-out portion 100. In the following description, a position closer to the core yarn bobbin holding portion 50 in the core yarn running direction is referred to as the upstream position, and a position closer to the core yarn guiding portion 52 is referred to as the downstream position.

[0041] The unit base 60 supports a core yarn detection device 90, a slack ensuring unit 80, a tension applying unit 70, and a core yarn let-off unit 100. A linear normal yarn path is formed on the unit base 60 during supply of the core yarn C. The core yarn detection device 90, the tension applying unit 70, and the core yarn let-off unit 100 are arranged along the normal yarn path. A core yarn guide 61 that guides the core yarn C is provided at the most upstream of the unit base 60.

[0042] The tension applying unit 70 applies tension to the core yarn C while the core yarn C is being supplied. The tension applying unit 70 applies tension to the core yarn C downstream of the core yarn guide 61 in the core yarn running direction. The tension applying unit 70 has a fixed piece 73 in the shape of a rectangular box that opens upward, and a movable piece 74 that is rotatably attached to the fixed piece 73. The movable piece 74 is biased in a direction that opens from the fixed piece 73 by a spring (not shown) provided on the fixed piece 73. The fixed piece 73 is provided with a plurality of shafts (not shown) that are perpendicular or substantially perpendicular to the core yarn running direction, and the plurality of shafts are provided at predetermined intervals along the core yarn running direction. A hole is formed at each tip of a plurality of protrusions provided on the movable piece 74 (none are shown). The core yarn C is alternately hung on these shafts and holes. Therefore, as shown in FIG. 3, when the movable piece 74 opens with respect to the fixed piece 73, the core yarn C is bent multiple times. In this state, when the core yarn C is pulled downstream by the draft device 6 and the air spinning device 7 (i.e., when the core yarn C is running), tension is applied to the core yarn C downstream of the tension application unit 70 (including the tension application unit 70) in the core yarn running direction. The state of the tension application unit 70 at this time is referred to as a tension applied state.

[0043] When the movable piece 74 closes relative to the fixed piece 73, the core yarn C becomes substantially straight. As a result, the tension applied to the core yarn C downstream of the tension applying unit 70, including the tension applying unit 70, is released (or the tension becomes close to zero). The state of the tension applying unit 70 at this time is referred to as a non-tension applying state. The tension applying unit 70 has an operating member 75 for rotating the movable piece 74, and an air cylinder 76 (see FIG. 5). The operating member 75 is moved by the air cylinder 76 to come into contact with and separate from the movable piece 74. When air is supplied to the air cylinder 76, the operating member 75 moves downward (in the direction in which the movable piece 74 closes relative to the fixed piece 73). As a result, the movable piece 74 closes, and the tension applying unit 70 is switched to a non-tension applying state. When the supply of air to the air cylinder 76 is stopped, the operating member 75 is moved away from the movable piece 74 and upward (in the direction in which the movable piece 74 opens relative to the fixed piece 73). This causes the movable piece 74 to open, and the tension applying section 70 is switched to the tension applying state.

[0044] As shown in FIG. 3, the slack ensuring section 80 is provided between the core yarn bobbin holding section 50 (see FIG. 2) and the core yarn let-off section 100 in the core yarn running direction. The slack ensuring section 80 provides slack to the core yarn C downstream of the tension applying section 70 in the core yarn running direction. The slack ensuring section 80 ensures slack in the core yarn C downstream of the tension applying section 70 in the core yarn running direction. The slack ensuring section 80 has an arm 81 and an air cylinder 82. The arm 81 is rotatably attached to the unit base 60 via a support shaft 81c. The arm 81 is rotated by the air cylinder 82. When air is supplied to the air cylinder 82, the tip end 81b of the arm body 81a is moved to a position (the position indicated by the two-dot chain line in FIG. 3) away from the normal yarn path. At this time, the arm 81 is disposed at the slack ensuring position P2. When the supply of air to the air cylinder 82 is stopped, the tip 81b of the arm body 81a is moved to the running path (position indicated by the solid line in FIG. 3) of the core yarn C. At this time, the arm 81 is disposed at the normal position P1.

[0045] As shown in Fig. 3 and Fig. 4, the arm 81 has an arm body 81a, for example, in the form of a long and thin plate extending from a fulcrum part 81e supported by a support shaft 81c, and an adjustment part 85 attached to a tip part 81b of the arm body 81a. A plate-shaped first protrusion 83 extending perpendicularly from the arm body 81a is provided at the tip part 81b of the arm body 81a. The adjustment part 85 is attached to the tip part 81b of the arm body 81a via a support shaft 85c so as to be rotatable. The support shaft 85c of the adjustment part 85 is parallel to the support shaft 81c of the arm body 81a. The adjustment part 85 can be fixed to the arm body 81a in each of a state where it is deployed with respect to the arm body 81a (see Fig. 3, Fig. 4 and Fig. 6) and a state where it is rotated and retracted with respect to the arm body 81a (see Fig. 8).

[0046] The adjustment portion 85 includes, for example, a plate-shaped base piece 85a that partially overlaps the tip end 81b of the arm body 81a. The base piece 85a is attached on the opposite side to the first protrusion 83, and the adjustment portion 85 does not interfere with the first protrusion 83. As shown in Figs. 3 and 4, the base piece 85a protrudes from the tip end 81b of the arm body 81a along an imaginary extension plane of the arm body 81a when the adjustment portion 85 is unfolded. A plate-shaped second protrusion 84 that extends perpendicularly to the base piece 85a is provided at the tip of the base piece 85a. When the adjustment portion 85 is unfolded, the first protrusion 83 and the second protrusion 84 are, for example, parallel to each other. When the arm 81 is disposed in the normal position P1, the first protrusion 83 and the second protrusion 84 intersect with the normal yarn path of the core yarn C. The first protrusion 83 is formed with a circular first engagement hole 83a through which the core yarn C passes. The second projecting piece 84 is formed with a circular second engagement hole 84a through which the core yarn C passes. The first engagement hole 83a and the second engagement hole 84a are two core yarn engagement parts (core yarn passing parts) provided at the tip of the arm 81.

[0047] When the arm 81 is disposed in the slack ensuring position P2, slack is ensured in the core yarn C. The state of the slack ensuring section 80 when the arm 81 is disposed in the slack ensuring position P2 is referred to as the slack ensuring state. The state of the slack ensuring section 80 when the arm 81 is disposed in the normal position P1 is referred to as the non-slack ensuring state.

[0048] The core yarn let-off section 100 has the functions of delivering the core yarn C to the draft device 6, clamping the core yarn C, and cutting the core yarn C. The downstream end (outlet) of the core yarn let-off section 100 is provided to face a position between the middle roller pair 16 and the front roller pair 17 of the draft device 6, via the core yarn guiding section 52. The core yarn let-off section 100 has a clamping section 106 (see FIG. 3), a cutter (not shown), and an air cylinder 108 (see FIG. 5).

[0049] The core yarn let-off section 100 sends out the core yarn C to the draft device 6 downstream of the tension applying section 70 and the slack ensuring section 80 in the core yarn running direction. "Sending out the core yarn C" refers to the operation of the core yarn let-off section 100 sending out the core yarn C (the yarn end of the core yarn C) to the draft device 6 when the supply of the core yarn C starts (restarts). "Supplying the core yarn C" refers to the operation of the core yarn supplying device 200 continuously supplying the core yarn C to the draft device 6 while applying tension to the core yarn C after the supply of the core yarn C starts (restarts) (after the core yarn C is let-off by the core yarn let-off section 100) (i.e., the operation during spinning).

[0050] The clamp unit 106 clamps the core yarn C (the yarn end of the core yarn C) in the core yarn let-off unit 100. The cutter has a function of cutting the core yarn C clamped by the clamp unit 106.

[0051] When air is supplied to the air cylinder 108 (see FIG. 5), the clamp unit 106 clamps the core yarn C. The state of the clamp unit 106 at this time is called the clamped state. When the supply of air to the air cylinder 108 is stopped, the clamp unit 106 releases the core yarn C. The state of the clamp unit 106 at this time is called the unclamped state.

[0052] The cutter cuts the core yarn C downstream of the clamp unit 106 in the core yarn running direction. The cutter is operated in conjunction with the clamp unit 106 by an air cylinder 108. The cutter cuts the core yarn C when the clamp unit 106 is switched from the non-clamped state to the clamped state.

[0053] 3, the core yarn detection device 90 detects the state of the core yarn C, for example, at a position upstream of the tension applying unit 70 in the core yarn traveling direction. For example, the core yarn detection device 90 detects the presence or absence of the core yarn C as the state of the core yarn C. In this way, the core yarn detection device 90 can detect breakage of the core yarn C and / or the absence of the core yarn C in the core yarn package CP. A core yarn guide 62 that guides the core yarn C is disposed upstream of the core yarn detection device 90 in the core yarn traveling direction.

[0054] The core yarn detection device 90 is an optical sensor having a light-projecting unit 91 and a light-receiving unit 92. The light-projecting unit 91 projects light onto the core yarn C passing through the core yarn detection device 90. The light-projecting unit 91 is configured, for example, with a light-emitting diode. The light projection of the light-projecting unit 91 is controlled by the unit controller 10. A yarn path is formed between the light-projecting unit 91 and the light-receiving unit 92. The core yarn detection device 90 detects the state of the core yarn C traveling along the yarn path in a non-contact manner.

[0055] The light receiving unit 92 receives, of the light from the light projecting unit 91, that has passed through the core yarn C. The light receiving unit 92 is, for example, a photodiode, converts the intensity of the received light into an electrical signal, and outputs the electrical signal to the unit controller 10. Note that the light receiving unit 92 may receive, of the light from the light projecting unit 91, that has been reflected by the core yarn C. For example, the configurations described in Patent Document 1 above or other known configurations can be adopted for the core yarn detection device 90, the tension applying unit 70, and the core yarn letting-out unit 100.

[0056] 4, the core yarn supplying unit 51 further includes a clamp device 110 provided between the core yarn bobbin holding part 50 and the slack ensuring part 80 in the core yarn running direction. In other words, the clamp device 110 is disposed upstream of the first engagement hole 83a (the first engagement hole 83a and the second engagement hole 84a when the adjustment part 85 is deployed) of the slack ensuring part 80 located in the normal position P1 in the core yarn running direction. The core yarn supplying unit 51 further includes a guide part 120 disposed adjacent to and downstream of the clamp device 110 in the core yarn running direction.

[0057] The clamp device 110 is disposed between the tension applying section 70 and the slack ensuring section 80. In other words, the clamp device 110 is disposed between the tension applying section 70 and the first engagement hole 83a of the slack ensuring section 80 located at the normal position P1. The clamp device 110 has a receiving section 114, a frame section 112, and a clamp bar 113. The receiving section 114 is a plate-shaped member extending parallel to the normal yarn path, and is fixed to a base plate 121 (described later) of the guide section 120. The frame section 112 is disposed so as to surround the receiving section 114. The receiving section 114, the frame section 112, and the clamp bar 113 are made of, for example, ceramic. The normal yarn path of the core yarn C is located between the receiving section 114 and the clamp bar 113. When the clamp bar 113 is located at the standby position, the clamp bar 113 is separated from the normal yarn path of the core yarn C. The receiving portion 114 is also spaced apart from the normal yarn path of the core yarn C. A rubber member 116 such as a rubber pad is attached to the receiving portion 114. The rubber member 116 may be provided so as to surround the receiving portion 114, but is attached at least to the surface of the receiving portion 114 that faces the normal yarn path.

[0058] The clamp device 110 has an air cylinder 118 (see FIG. 5). The frame portion 112 is attached to the tip of the inflatable shaft 111 that can reciprocate in a direction perpendicular to the yarn path. The frame portion 112 is urged upward (in a direction away from the base end surface of the yarn path guide 95) by, for example, a spring (not shown). When air is supplied to the air cylinder 118, the frame portion 112 descends via the inflatable shaft 111, and the core yarn C is clamped between the clamp bar 113 and the receiving portion 114 (see FIG. 7). The state of the clamp device 110 at this time is called a clamped state. When the supply of air to the air cylinder 118 is stopped, the frame portion 112 ascends via the inflatable shaft 111, and the clamp bar 113 leaves the core yarn C (see FIG. 4). The state of the clamp device 110 at this time is called a non-clamped state.

[0059] The clamp device 110 is a return prevention unit that prevents the slack-secured portion of the core yarn C, whose slack has been secured by the slack securing unit 80, from returning in the direction opposite to the core yarn traveling direction. The clamp device 110 prevents the slack-secured portion of the core yarn C, whose slack has been secured by the slack securing unit 80, from returning upstream of the clamp device 110 (i.e., toward the tension applying unit 70). The clamped state corresponds to a return prevention state in which the slack-secured portion of the core yarn C is prevented from returning. The unclamped state corresponds to an open state in which the slack-secured portion of the core yarn C is released.

[0060] The guide section 120 has a base plate 121, a yarn passing section 122a, and a pair of deviation restriction pieces 122. The base plate 121 has a fixed section provided parallel to the base end surface of the yarn path guide 95, and a main section extending perpendicularly from the fixed section. The yarn passing section 122a is formed in the center of the width direction of the main section of the base plate 121. The pair of deviation restriction pieces 122 are provided continuously on the upper part of the base plate 121 (opposite the fixed section), and extend parallel to each other so as to cover the clamp bar 113. The core yarn C that normally travels on the yarn path passes through the yarn passing section 122a. The pair of deviation restriction pieces 122 restrict the travel path of the core yarn C. When the slack ensuring section 80 is switched to the slack ensuring state, the core yarn C moves near a fan-shaped area centered on the rotation range of the tip end 81b of the arm 81. The core yarn C is always disposed between the pair of deviation restriction pieces 122 (see FIG. 7). The pair of deviation restriction pieces 122 restrict the core yarn C from deviating from the fan-shaped region in the left-right direction (the axial direction of the support shaft 81c).

[0061] The guide portion 120 has a plate-shaped yarn path guide 123 that is disposed between the first protrusion 83 and the second protrusion 84 when the arm 81 is disposed in the normal position P1. The yarn path guide 123 is formed with a circular yarn passage hole 123a.

[0062] A plate-shaped yarn guide 95 is provided at the downstream end of the unit base 60 between the yarn guide 123 and the core yarn let-off section 100. A V-shaped engagement groove 95a, for example, is formed at the tip of the yarn guide 95. The engagement groove 95a guides the core yarn C as the core yarn C comes into contact with the top or oblique side of the engagement groove 95a.

[0063] As shown in FIG. 3, the core yarn supplying unit 51 further includes a first air supply pipe 54, a second air supply pipe 55, a relay board 56, and a multi-core cable 57.

[0064] 5, the first air supply pipe 54 connects an air supply pipe connected to an air supply source (not shown) via an air supply unit of the second end frame 5, and a plurality of air supply pipes connected to each of the air cylinders 118, 76, 82, 108. As a result, air is supplied from the first end frame 4 to each of the air cylinders 118, 76, 82, 108 via the first air supply pipe 54.

[0065] A first solenoid valve 58 is attached to the first air supply pipe 54. The first solenoid valve 58 supplies and stops the air supplied from the first end frame 4 to each of the air cylinders 118, 76, 82, 108. For example, when the yarn monitoring device 8 detects a yarn defect and stops the production of the yarn Y in the spinning unit 2, the first solenoid valve 58 is opened, and the clamp device 110 is switched to the clamped state, the tension applying unit 70 to the non-tensioned state, the slack ensuring unit 80 to the slack ensuring state, and the clamp unit 106 to the clamped state. At this time, as shown in Figs. 6 and 7, the yarn passing portion 122a, the yarn passing hole 123a, and the engagement groove 95a are aligned substantially in a straight line, but the first protrusion 83 and the second protrusion 84 move upward away from the area between the base plate 121 and the yarn path guide 95. The core yarn C is clamped by the clamp bar 113 and the receiving portion 114, and passes through the first engagement hole 83a, the thread passing hole 123a, and the second engagement hole 84a. When the arm 81 is placed in the slack ensuring position P2, the core yarn C is bent four times by the clamp bar 113, the first engagement hole 83a, the thread passing hole 123a, and the second engagement hole 84a.

[0066] When the spinning unit 2 starts (resumes) the production of the yarn Y, the first solenoid valve 58 is closed, the clamp device 110 is switched to the unclamped state, the tension applying unit 70 is switched to the tension applying state, the slack ensuring unit 80 is switched to the slack non-ensuring state, and the clamp unit 106 is switched to the unclamped state. At this time, as shown in Figs. 3 and 4, the yarn passing unit 122a, the first engagement hole 83a, the yarn passing hole 123a, the second engagement hole 84a, and the engagement groove 95a are aligned substantially in a straight line. The core yarn C passes through the space between the clamp bar 113 and the receiving unit 114 without contacting it, and further passes through the insides of the yarn passing unit 122a, the first engagement hole 83a, the yarn passing hole 123a, and the second engagement hole 84a, and is guided by the engagement groove 95a. When the arm 81 is located at the normal position P1, the yarn path guide 123, the first engagement hole 83a, and the second engagement hole 84a are located on the normal yarn path.

[0067] The second air supply pipe 55 connects an air supply pipe connected to an air supply source and an air supply pipe connected to the core yarn let-off section 100. As a result, air is supplied from the second end frame 5 to the core yarn let-off section 100 via the second air supply pipe 55.

[0068] A second solenoid valve 59 is attached to the second air supply pipe 55. The second solenoid valve 59 supplies and stops air supplied from the second end frame 5 to the core yarn let-off section 100. When starting (resuming) production of the yarn Y in the spinning unit 2, the second solenoid valve 59 is opened. As a result, air is injected into the travel path of the core yarn C inside the core yarn let-off section 100, and the core yarn C is let-off from the core yarn let-off section 100. When the second solenoid valve 59 is closed, the injection of air into the travel path of the core yarn C in the core yarn let-off section 100 stops, and the let-off operation of the core yarn C by the core yarn let-off section 100 also stops.

[0069] The relay board 56 is electrically connected to each of the core yarn detection device 90, the first solenoid valve 58, and the second solenoid valve 59.

[0070] The multi-core cable 57 electrically connects the relay board 56 and a multi-core cable (not shown) connected to the unit controller 10. This enables the unit controller 10 to control the core yarn supplying unit 51.

[0071] The operation of the above-mentioned core yarn supplying device 200 and the core yarn spinning method using the core yarn supplying device 200 will be described. As shown in Fig. 3, when the core yarn C is supplied, the core yarn C runs downstream in the core yarn running direction by being pulled by the draft device 6 and the air spinning device 7. At this time, the tension applying unit 70 is held in a tensioned state, and the core yarn C runs toward the draft device 6 while being tensioned by the tension applying unit 70. During the supply of the core yarn C, the slack ensuring unit 80 is in a slack non-ensuring state, and the clamp unit 106 is in an unclamped state.

[0072] 6, when at least one of the core yarn detection device 90, the yarn monitoring device 8, and the tension sensor 9 detects a yarn defect or the absence of a yarn (core yarn C or yarn Y), the unit controller 10 sends a control signal to the relay board 56 to interrupt the supply of the core yarn C, and the supply of the core yarn C is interrupted. Specifically, the first solenoid valve 58 is opened, and the clamp unit 106 of the core yarn let-off unit 100 is switched to a clamped state. In conjunction with this, the cutter of the core yarn let-off unit 100 is operated, and the core yarn C located downstream of the clamp unit 106 in the core yarn running direction is cut. The tension applying unit 70 is switched to a non-tensioned state, the slack ensuring unit 80 is switched to a slack ensuring state, and the clamp device 110 is switched to a clamped state. As a result, tension is released from the core yarn C, and slack in the core yarn C is ensured. Incidentally, even when the spinning by the spinning unit 2 is normally completed, a control signal for terminating the supply of the core yarn C is sent from the unit controller 10 to the relay board 56, and the same operation as above is carried out.

[0073] When the supply of the core yarn C starts, the first solenoid valve 58 is closed, the clamping section 106 is switched to the unclamped state, the tensioning section 70 is switched to the tensioning state, the clamping device 110 is switched to the unclamped state, and the slack ensuring section 80 is switched to the non-slack ensuring state. The second solenoid valve 59 is opened, and the core yarn C whose slack has been ensured by the slack ensuring section 80 is sent to the draft device 6 by the core yarn let-off section 100. This starts the supply of the core yarn C. The clamping device 110 switches from the return prevention state to the open state when the core yarn let-off section 100 starts to let-off the core yarn C. Note that the clamping device 110 may be switched from the return prevention state to the open state immediately after the core yarn let-off section 100 starts to let-off the core yarn C by adjusting the let-off timing of the core yarn C, for example. "Immediately after the start of the release of the core yarn C" means any point after the start of the release of the core yarn C until the slack portion of the core yarn C disappears and the core yarn C is positioned on the normal yarn path.

[0074] The core yarn let-off section 100 lets out a stretchable core yarn C toward a position between the middle roller pair 16 and the front roller pair 17. A yarn Y containing the core yarn C is produced by the draft device 6 and the air spinning device 7. During normal spinning, the core yarn let-off section 100 does not operate. The core yarn C is continuously supplied by the rotational drive of the front roller pair 17.

[0075] In the core yarn supplying device 200, the path length of the slack-securing portion of the core yarn C may be adjusted according to the magnitude (degree) of the stretchability of the core yarn C. As shown in FIG. 8, the path of the core yarn C can be changed so that the core yarn C does not pass through the second engagement hole 84a but only passes through the first engagement hole 83a by rotating and retracting the adjustment unit 85. The adjustment unit 85 can change the path length of the slack-securing portion of the core yarn C. The "path length of the slack-securing portion of the core yarn C" is the difference between the path length of the core yarn C in the slack-securing state and the path length of the core yarn C in the non-slack-securing state (the length of the normal yarn path). The "path length of the slack-securing portion of the core yarn C" may be rephrased as the amount of slack secured (or the amount of slack provided). The amount of slack secured may be adjusted by adjusting the displacement amount of the air cylinder 82 and the rotation amount (amount of lift) of the arm 81. In this case, the air cylinder 82 corresponds to the adjustment unit. The adjustment unit increases the amount of slack ensured as the core yarn C becomes more elastic. The adjustment unit decreases the amount of slack ensured as the core yarn C becomes less elastic.

[0076] The core yarn let-off unit 100 may adjust the let-off force according to the path length of the slack ensuring portion of the core yarn C. The let-off force of the core yarn let-off unit 100 may be adjusted by adjusting the pressure of the air supplied, or by adjusting the air supply time (the open time of the second solenoid valve 59). The longer the path length of the slack ensuring portion of the core yarn C, the stronger the let-off force of the core yarn let-off unit 100. The shorter the path length of the slack ensuring portion of the core yarn C, the weaker the let-off force of the core yarn let-off unit 100.

[0077] The path length of the slack-ensuring portion of the core yarn C is preferably 1 to 3 times the distance between the clamping portion 106 of the core yarn let-off portion 100 and the top roller of the front roller pair 17. If the distance is shorter than 1, the core yarn C let-off by the core yarn let-off portion 100 may not reach the draft device 6. If the distance is longer than 3 times, the core yarn C may become entangled with surrounding components when let-off by the core yarn let-off portion 100. The criteria for the distance, i.e., the start point and the end point, will be explained more precisely. The start point of the distance is the downstream end point of the area (clamping surface) of the clamping portion 106 that clamps the core yarn C. The end point of the distance is the nip point of the front roller pair 17.

[0078] According to the core yarn supplying device 200, the spinning machine 1, and the core yarn spinning method of the present embodiment, a package P with very few seams is formed. As shown in FIG. 9(a), in the present embodiment, the interval between the multiple seams included in the yarn Y in the package P is longer than the interval L between the periodic seams caused by the bob yarn replacement. FIG. 9(b) shows the interval L between the periodic seams Z caused by the bob yarn replacement for the package PX of the reference embodiment. That is, the package P does not include seams in the period L corresponding to the formation of seams due to the bob yarn replacement. In the example shown in FIG. 9(a), the number of seams in the package P is small, so the seams are not shown. "Both yarn replacement" is an operation performed in the process of rewinding the bob yarn (spinning bobbin) wound by the ring spinning machine into a package by an automatic winder, and is an operation of replacing one bob yarn with the next bob yarn after rewinding it. The end of one bob yarn and the beginning of the next bob yarn are joined by a yarn joining device of the automatic winder, and as a result, a seam is generated. Since the automatic winder rewinds a plurality (a large number) of bobbins while forming one package, the number of joints included in the package formed by the automatic winder is greater than that in this embodiment.

[0079] In this embodiment, the package P does not have any seams resulting from replacement of the core yarn package CP, but such seams may be included. Even if such seams are included, the total length of the core yarn C wound around one core yarn package CP is generally longer than the total length of one bobbin. Therefore, even if the package P includes seams resulting from replacement of the core yarn package CP, the number of such seams will be small.

[0080] According to the core yarn supplying device 200 of this embodiment, the clamp device 110 (return prevention unit) provided at a position upstream of the slack ensuring unit 80 in the core yarn traveling direction prevents the slack ensuring portion of the core yarn C from returning upstream. Therefore, even when a stretchable core yarn C is used, the core yarn let-off unit 100 can achieve an appropriate let-off distance of the core yarn. This allows the core yarn C to be appropriately supplied to the draft device 6.

[0081] At the start of or after the core yarn C is let out by the core yarn let-out section 100, the clamp device 110 (return prevention section) switches from the return prevention state to the open state. This makes it possible to reliably prevent the slack-secured portion of the core yarn C from returning upstream when the core yarn C is let out.

[0082] The clamp device 110 serving as a return prevention section physically clamps the core yarn C, thereby preventing the core yarn C from returning upstream.

[0083] According to the configuration in which the core yarn supplying device 200 includes the tension applying unit 70, the core yarn C can be supplied suitably.

[0084] In the layout of the above embodiment, the distance between the slack ensuring portion 80 and the clamp device 110 is short, which reduces the propagation of the shrinkage of the core yarn C. As a result, a decrease in the amount of slack can be avoided.

[0085] By bending the core thread C into an M shape by the slack ensuring portion 80, a large amount of slack can be ensured in a small space.

[0086] By adjusting the path length of the slack ensuring portion according to the elasticity of the core yarn C using the adjustment unit 85 or the like, the core yarn C can be appropriately supplied to the draft device 6 regardless of the type of the core yarn C.

[0087] By changing the feeding force in the core yarn let-off section 100 according to the elasticity of the core yarn C, the core yarn C can be properly let-off to the draft device 6 regardless of the type of the core yarn C.

[0088] According to the spinning machine 1 of the present embodiment, by the above-mentioned action, the core yarn C can be appropriately supplied to the draft device 6. The yarn Y containing the stretchable core yarn C can be appropriately produced to form the package P.

[0089] The path length of the slack ensuring portion of the core yarn C formed by the slack ensuring unit 80 is from 1 to 3 times the distance from the clamp unit 106 of the core yarn let-off unit 100 to the top roller of the front roller pair 17. This ensures that the core yarn C let-off by the core yarn let-off unit 100 reaches the front roller pair 17 reliably.

[0090] Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. The above embodiment and the following modified examples may be appropriately combined.

[0091] For example, when the slack is ensured by the slack ensuring unit 80 (i.e., while the supply of the core yarn C is stopped), the tension providing unit 70 may provide tension to the core yarn C, thereby functioning as a return prevention unit. In this case, the magnitude of tension provided by the tension providing unit 70 to the core yarn C may be different from the magnitude of tension provided during normal spinning. Unlike the above embodiment, the air system of the tension providing unit 70 may be a system separate from the core yarn sending-out unit 100 and the slack ensuring unit 80, or the tension providing unit 70 may be modified to a mechanism in which the movable piece 74 is closed by supplying air. According to this configuration, the tension providing unit 70 provides tension to the core yarn C while the core yarn C is being supplied, and prevents the slack ensuring portion from returning before the core yarn C is sent out (i.e., while the supply of the core yarn C is stopped). Since the tension providing unit 70 has two functions, the clamp device 110 of the above embodiment may be omitted.

[0092] In the above embodiment, the slack ensuring section 80 has an arm 81 rotatably attached to the unit base 60 (base section). However, a slack ensuring section having an arm movably attached to the base section may be used. In that case, the support shaft 81c does not exist. The arm may be provided so that the entire arm moves toward and away from the base section (so that it moves in a translational manner). A moving means (drive section) for moving the arm may be provided separately from the air cylinder 82. When the arm is placed in the slack ensuring position, one or two core yarn passing sections formed on the arm move away from the guide section 120 and the clamp device 110. At that time, the core yarn C is bent multiple times.

[0093] In the above embodiment, an example has been described in which the adjustment portion 85 is provided in the slack ensuring portion 80. However, the adjustment portion 85 may be omitted. The first protruding piece 83 having the first engagement hole 83a and the second protruding piece 84 having the second engagement hole 84a may be integrally formed in the tip portion 81b of the arm body 81a. That is, two core yarn passing portions may be integrally formed in the arm 81, and the path length of the slack ensuring portion may be determined by the arrangement of the two core yarn passing portions. The two core yarn passing portions are not limited to being circular holes, and may be elliptical or polygonal holes, or may have a notch shape (V-shape) with which the core yarn C can be engaged.

[0094] The tension applying portion 70 may be omitted. The location of the clamp device 110 is not limited to between the tension applying portion 70 and the slack ensuring portion 80, and may be changed as appropriate.

[0095] The slack ensuring section 80 may be called by another name. After the operation of the slack ensuring section 80, the core yarn C is slacker than before the operation. However, the degree of slackness of the core yarn C may differ depending on the core yarn C. The slack ensuring section 80 may be called, for example, a "core yarn detouring section" or a "path detouring section" based on the meaning that it detouring the core yarn C. The slack ensuring section 80 may be called, for example, a "retention length expanding section" based on the meaning that it expands the retention length that holds the core yarn C. The slack ensuring section 80 may be called, for example, a "core yarn path moving section" based on the meaning that it moves the path of the core yarn C.

[0096] In the above embodiment, the draft device 6 includes the back roller pair 14, the third roller pair 15, the middle roller pair 16, and the front roller pair 17. However, one or more roller pairs may be provided upstream of the back roller pair 14. The front roller pair (the roller pair disposed at the position closest to the air spinning device 7 in the transport path of the fiber bundle F) may be configured as a part of another device. For example, the spinning unit 2 may include a supply device that supplies the fiber bundle F drafted by the draft device 6 to the air spinning device 7, and the front roller pair 17 may be included as a part of the supply device. The front roller pair 17 may be included in the draft device 6 that drafts the fiber bundle S or in the supply device that supplies the fiber bundle F to the air spinning device 7, or may be provided independently without being included in another device.

[0097] In the spinning unit 2, the yarn pooling device 11 has a function of drawing out the yarn Y from the air spinning device 7, but the yarn Y may be drawn out from the air spinning device 7 by a delivery roller and a nip roller. When drawing out the yarn Y from the air spinning device 7 by a delivery roller and a nip roller, instead of or in addition to the yarn pooling device 11, a slack tube using suction air flow and / or a mechanical compensator, etc. may be provided.

[0098] In the spinning unit 2, instead of connecting the two yarn ends using the yarn joining device 26, the yarn Y from the package P may be inserted into the air spinning device 7, and the drafting operation of the draft device 6 and the spinning operation of the air spinning device 7 may be started to connect (piecing) the yarn Y from the air spinning device 7 and the yarn Y of the package P.

[0099] In the spinning machine 1, the devices are arranged in the machine height direction such that the yarn Y supplied at the upper side is wound at the lower side. However, the devices may be arranged such that the yarn Y supplied at the lower side is wound at the upper side.

[0100] In the spinning machine 1, at least one of the bottom rollers of the draft device 6 and the traverse guide 23 are driven by power from the second end frame 5 (i.e., commonly for the multiple spinning units 2). However, each part of the spinning unit 2 (e.g., the draft device 6, the air spinning device 7, the winding device 13, etc.) may be driven independently for each spinning unit 2.

[0101] In the running direction of the yarn Y, the tension sensor 9 may be disposed upstream of the yarn monitoring device 8. The unit controller 10 may be provided for each spinning unit 2. In the spinning unit 2, at least one of the waxing device 12, the tension sensor 9, and the yarn monitoring device 8 may be omitted. When wax is not applied to the yarn Y, the waxing device 12 does not need to be omitted, and only the wax may be removed from the waxing device 12.

[0102] In Fig. 1, the spinning machine 1 is illustrated as winding a cheese-shaped package P, but it is also possible to wind a cone-shaped package. In the case of a cone-shaped package, slack occurs in the yarn Y due to the traverse of the yarn Y, but the slack can be absorbed by the yarn pooling device 11. The materials and shapes of each component are not limited to those described above, and various materials and shapes can be adopted. [Explanation of symbols]

[0103] 1...spinning machine (air spinning machine), 2...spinning unit, 6...draft device, 7...air spinning device (air jet spinning device), 50...core yarn bobbin holding section, 51...core yarn supplying unit, 60...unit base (base section), 70...tensioning section, 80...slack ensuring section, 81...arm, 82...air cylinder (driving section), 83a...first engagement hole (core yarn passing section), 84a...second engagement hole (core yarn passing section), 100...core yarn feed-out section, 106...clamping section, 100...core yarn feed-out section, 110...clamping device (return prevention section), 200...core yarn supplying device, C...core yarn, CP...core yarn package, F...fiber bundle, P...package, Y...yarn.

Claims

1. a core bobbin holding section for holding a core bobbin around which a core thread is wound; A core yarn delivery section that delivers the core yarn; a slack ensuring portion that ensures slack in the core yarn, the slack ensuring portion being provided between the core yarn bobbin holding portion and the core yarn letting-out portion in the running direction of the core yarn; a return prevention section that is provided between the core yarn bobbin holding section and the slack ensuring section in the running direction and prevents the slack ensured portion of the core yarn, the slack of which has been ensured by the slack ensuring section, from returning in the direction opposite to the running direction.

2. The return prevention unit can be switched between a return prevention state in which the return of the slack ensuring portion of the core yarn is prevented and an open state in which the slack ensuring portion of the core yarn is free, The core yarn supplying device according to claim 1 , wherein the return prevention section switches from the return prevention state to the open state when or immediately after the core yarn let-off section starts to let-off the core yarn.

3. The core yarn supplying device according to claim 1 or 2, wherein the return prevention portion is a clamping device that clamps the core yarn.

4. The core yarn supplying device according to claim 1 or 2, further comprising a tension applying section provided between the core yarn bobbin holding section and the core yarn letting-off section in the running direction, the tension applying section applying tension to the core yarn while the core yarn is being supplied.

5. The core yarn supplying device according to claim 3 , further comprising a tension applying section provided between the core yarn bobbin holding section and the core yarn letting-off section in the running direction, the tension applying section applying tension to the core yarn while the core yarn is being supplied.

6. The core yarn supplying device according to claim 5 , wherein the clamp device is disposed between the tension applying portion and the slack ensuring portion in the traveling direction.

7. The core yarn supplying device according to claim 4 , wherein the tension applying section functions as the return prevention section by applying tension to the core yarn while the supply of the core yarn is stopped.

8. A base portion supporting the slack securing portion is further provided, At least one yarn path guide is fixed to the base portion to guide the core yarn so that the core yarn travels along a linear normal yarn path during supply of the core yarn, The slack ensuring portion is an arm movably attached to the base portion and having two core yarn passing portions; A drive unit that moves the arm, When the arm is disposed at the normal position, the yarn path guide and the two core yarn passing portions are disposed on the normal yarn path, The core yarn supplying device according to any one of claims 1 to 7, wherein when the arm is disposed in the slack-ensuring position, the core yarn is bent and guided at least four times.

9. The core yarn supplying device according to any one of claims 1 to 8, wherein the slack ensuring section is provided with an adjustment section capable of adjusting a path length of the slack ensuring portion of the core yarn.

10. The core yarn supplying device according to any one of claims 1 to 9, wherein the core yarn let-off section changes a let-off force depending on a path length of the slack ensuring portion of the core yarn.

11. A core yarn supplying device according to any one of claims 1 to 10, A draft device for drafting the fiber bundle; an air jet spinning device that spins a fiber bundle drafted by the draft device using the core yarn supplied from the core yarn supplying device as a core to produce a yarn containing the core yarn; a winding device for winding the yarn into a package, The core yarn let-off section of the core yarn supplying device is provided at a position between a middle roller pair and a front roller pair of the draft device so as to face the position.

12. 12. The air spinning machine according to claim 11, wherein a length of the slack ensuring portion of the core yarn formed by the slack ensuring portion is greater than or equal to 1 time and less than or equal to 3 times the distance between a clamp portion in the core yarn let-out portion and a top roller of the front roller pair.

13. a core yarn supplying device including: a core yarn bobbin holding section which holds a core yarn bobbin around which a core yarn is wound; a core yarn sending-out section which sends out the core yarn; a slack ensuring section which is provided between the core yarn bobbin holding section and the core yarn sending-out section in the running direction of the core yarn and ensures slack in the core yarn; and a return prevention section which is provided between the core yarn bobbin holding section and the slack ensuring section in the running direction and prevents a slack ensured portion of the core yarn, the slack of which is ensured by the slack ensuring section, from returning in a direction opposite to the running direction; A draft device for drafting the fiber bundle; an air jet spinning device for spinning a fiber bundle drafted by the draft device using the core yarn supplied from the core yarn supplying device as a core to produce a yarn containing the core yarn, The core yarn having elasticity is fed from the core yarn feed-out section provided at a position between a middle roller pair and a front roller pair of the draft device so as to face each other, A core yarn spinning method, comprising producing a yarn containing the core yarn by an air jet spinning device.

14. A package wound with a yarn containing an elastic core yarn produced by air jet spinning, A package in which the intervals between multiple joints included in the yarn are longer than the intervals between periodic joints caused by bob yarn replacement, and the yarn does not have any joints caused by core yarn replacement.

Images