JP7314741B2 - Yarn splicing method for roving, splicing device, and roving - Google Patents

Description

TECHNICAL FIELD The present invention relates to a roving splicing method, a splicing device for carrying out the splicing method, and a technique of a roving spliced by the splicing method.

BACKGROUND ART Conventionally, glass fibers have been used as raw materials for industrial products such as printed wiring boards and glass fiber reinforced plastics (FRP, FRTP).
Glass fiber is mainly obtained by spinning molten glass, and several tens to thousands of glass fiber monofilaments with a diameter of several μm to several tens μm are bundled to form a glass fiber bundle called a strand, and the strand is once wound on a drum and processed into a state called a cake.
The strands are then unwound from the cake and processed into a twisted glass yarn form, or a roving form in which a plurality of strands are bundled and plied and then rewound into a cylindrical shape, and then shipped.

Here, in the manufacturing process of a roving made of a yarn in which strands (glass fiber bundles) pulled out from a plurality of cakes are bundled and combined, for example, when the strands wound around the cake are used up and replaced with a new cake, or when the strand pulled out from the cake is unexpectedly cut, the number of strands constituting the yarn decreases, and a part of the yarn has a narrowed portion with a reduced diameter.
As described above, when a reduced diameter portion occurs in a portion of a yarn, splicing is required to restore the reduced diameter portion to a normal thickness. Therefore, various techniques have been disclosed for splicing devices (splicers) that automatically splice yarns by intertwining a spare strand (hereinafter referred to as "preliminary strand") with the reduced diameter portion of the yarn.

For example, Patent Document 1 discloses a technique for a splicing device that includes a splicing space forming portion that forms a splicing space for splicing yarns, and a gas injection portion that sprays gas into the splicing space.
In the splicing device, the splicing space forming section is configured such that (L1/L2)>1, where L1 is the length of the splicing space in the running direction of the yarn, and L2 is the length of the splicing space in the direction perpendicular to the running direction.
With such a configuration, an ideal swirl flow is generated in the splicing space, and the swirl flow causes the preliminary strand to ideally swirl around the yarn toward the downstream side in the running direction and efficiently entangle the yarn.
As a result, the splicing device can improve the efficiency of splicing and the tensile strength of the spliced portion (the force with which the spliced portion is pulled apart; the same shall apply hereinafter).

JP 2014-34466 A

In recent years, the product specifications required for glass fibers have become more and more diverse, and there are rovings with a larger count than the conventional mainstream rovings.
When the number of strands increases or the number of strands per strand increases, it becomes difficult to efficiently intertwine the preliminary strands with the yarn even if the yarn splicing device in Patent Document 1 is used, so splicing may not be performed or the tensile strength of the spliced portion may decrease.

SUMMARY OF THE INVENTION The present invention has been made in view of the problems of the present situation as described above, and it is an object of the present invention to provide a roving splicing method capable of achieving a high splicing success rate and high tensile strength at the spliced portion, a splicing device that implements the splicing method, and a roving having a high tensile strength at the spliced portion.

The problems to be solved by the present invention are as described above, and the means for solving these problems will now be described.

That is, the splicing method for roving according to the present invention uses a splicing device that includes a splicing space forming section that forms a splicing space for splicing a yarn formed by arranging a plurality of strands, and a gas injection section that injects gas into the splicing space. A roving yarn splicing method in which the preliminary strand is intertwined with a yarn, and then the preliminary strand, which is arranged to protrude from the yarn splicing space on the downstream side in the running direction of the yarn, is entangled with the yarn, wherein the preliminary strand is arranged such that the length L2 of the preliminary strand protruding from the splicing space with respect to the length L1 in the running direction in the splicing space satisfies (L2/L1)>3.

As described above, in the present invention, the length of the region of the preliminary strand on the downstream side in the running direction protruding from the splicing space (hereinafter referred to as the “surplus region” as appropriate) is set to be sufficiently long.
Therefore, even if it is difficult to efficiently entangle the preliminary strand with the yarn at a normal production speed due to its high rigidity, such as the above-mentioned roving with a larger count than conventional rovings, the surplus region of the preliminary strand will further wrap around the mutually entangled preliminary strand and the yarn in a manner to cover them while turning.
As a result, the portion where the yarn and the spare strand are entwined (hereinafter referred to as the "spliced portion" as appropriate) has a small bulk and is tightly entangled with each other, so that the spliced portion has a good tangled state, the success rate of splicing is improved, and the quality of the roving, which is the final product, can be improved.

Further, in the splicing method for rovings according to the present invention, it is preferable that the preliminary strand protruding from the splicing space passes through a predetermined yarn path during splicing.

With such a configuration, when the yarn is spliced in the splicing space, the surplus region of the preliminary strand passes through a predetermined position at the downstream end in the running direction of the yarn. By passing the surplus area of the spare strand through the predetermined yarn path, it is possible to suppress the surplus area from moving in a manner other than spiral movement due to the swirling flow of the gas injected from the gas injection part, and the success rate of splicing can be improved.

Further, in the splicing method for rovings according to the present invention, it is preferable to grip the vicinity of the tip end of the preliminary strand before splicing.

By gripping the vicinity of the tip of the preliminary strand in this manner, the preliminary strand is less likely to become entangled. Therefore, it is possible to prevent the preliminary strands from becoming entangled and the splicing failure.

Further, in the splicing method for rovings according to the present invention, it is preferable that the vicinity of the tip of the preliminary strand is gripped on the upstream side of the downstream end of the splicing space forming portion.

With such a configuration, the yarn in the splicing space is entangled with the preliminary strand, and thereafter, the preliminary strand held so as to protrude from the splicing space on the downstream side in the running direction of the yarn can be easily entangled with the yarn.

Further, the splicing device according to the present invention includes a splicing space forming part that forms a splicing space for splicing a yarn formed by arranging a plurality of strands, and a gas injection part that injects gas into the splicing space. By injecting gas into the splicing space from the gas injection part, a preliminary strand is entangled with the yarn and spliced. It is characterized by having a guide for making

With such a configuration, when the yarn is spliced in the splicing space, the surplus area of the preliminary strand passes through the predetermined yarn path. By passing the yarn path of the surplus area of the spare strand along the predetermined yarn path, it is possible to suppress the surplus area from moving in a manner other than a helical movement due to the swirling flow of the gas injected from the gas injection part, and the success rate of splicing can be improved.

Further, in the splicing device according to the present invention, it is preferable that the guide is arranged downstream of the splicing space.

By doing so, after the preliminary strand is entangled with the yarn in the yarn splicing space, the preliminary strand arranged so as to protrude from the yarn splicing space on the downstream side in the running direction of the yarn can be easily entangled with the yarn.

Further, a roving according to the present invention is a roving comprising a yarn composed of a plurality of strands pulled in one direction, a preliminary strand spliced to the yarn, and a splicing portion between the yarn and the preliminary strand, wherein the preliminary strand includes a first glass fiber portion intertwined with the yarn, and a downstream end of the yarn in the first glass fiber portion folded back and extended toward the upstream side. It is characterized by having a thread and a second glass fiber portion wound so as to cover the first glass fiber portion at the same time.

As described above, in the roving according to the present invention, the spliced portion has a spliced portion between the yarn and the preliminary strand, and is composed of the first glass fiber portion directly entwined with the yarn and the surplus region of the preliminary strand. Since the spliced portion is constituted by the second glass fiber portion wound so as to cover the yarn and the first glass fiber portion at the same time, the spliced portion has sufficient tensile strength.

Further, in the roving according to the present invention, it is preferable that (D1/D2)≧1, where D1 is the outer diameter of the cross section of the portion of the yarn where the preliminary strand is not spliced, and D2 is the outer diameter of the cross section of the first glass fiber portion of the preliminary strand.
In addition, the "outer diameter" here represents a circle-equivalent diameter.

With such a configuration, the outer diameter of the preliminary strand that is entangled with the yarn is set so as not to exceed the outer diameter of the yarn, and the rigidity of the preliminary strand is set so as not to exceed the rigidity of the yarn.
As a result, for example, it is possible to prevent the preliminary strand from being entangled with the yarn at the spliced portion, which is crushed by the preliminary strand, deforming the cross-sectional area of the entire roving, and lowering the tensile strength at the spliced portion.

Further, in the roving according to the present invention, it is preferable that the number of times of winding when the second glass fiber portion winds around the yarn and the first glass fiber portion in the preliminary strand is 3 or more.

With such a configuration, the second glass fiber portion of the preliminary strand can be more firmly wound around the region where the first glass fiber portion of the preliminary strand is entangled with the thread, and sufficient tensile strength can be imparted to the spliced portion formed in the roving.

In the roving according to the present invention, it is preferable that L4/D3≧15, where D3 is the average value of the cross-sectional outer diameter of the spliced portion of the yarn, and L4 is the length of the spliced portion.

By having such a configuration, it is possible to impart sufficient tensile strength to the spliced portion formed in the roving.

Further, in the roving according to the present invention, it is preferable that the count is 100 tex or more.

By setting it as such count, roving can be used for various uses.

As effects of the present invention, the following effects are obtained.
That is, according to the roving splicing method, the splicing device for carrying out the splicing method, and the roving spliced by the splicing method according to the present invention, it is possible to realize a spliced portion in which even glass fibers having a count larger than that of conventional ones are in a good entangled state. Therefore, the success rate of splicing is high, and the tensile strength of the spliced portion can be increased.

1 is a schematic configuration diagram showing the overall configuration of a roving manufacturing apparatus equipped with a splicing device according to an embodiment of the present invention; FIG. 1 is a diagram showing the overall configuration of a piecing device according to an embodiment of the present invention, where (a) is a side view thereof and (b) is a front view seen in the direction of arrow Y in FIG. 2(a). FIG. 4 is a diagram showing the operation procedure of the yarn splicing device over time, in which (a) is a side view showing a state in which yarn breakage has not occurred in a plurality of strands constituting the yarn, and (b) is a side view showing a state immediately after yarn breakage has occurred in the strands constituting the yarn. FIG. 10 is a diagram showing the operation procedure of the splicing device over time, in which (a) is a side view showing a state in which splicing is being performed on a broken yarn, and (b) is a side view showing a state immediately after the splicing by the splicing device is completed. FIG. 4 is a schematic diagram showing a state of a spliced portion of a roving spliced by a splicer.

Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 5. FIG.
1 to 4 is defined as the vertical direction of the roving manufacturing device 1 or the splicing device 5 for the sake of convenience. 1, 2(a), 3, and 4 is defined as the running direction of the yarn G. As shown in FIG. Furthermore, the direction of arrow A in FIG. 5 is defined as the direction indicating the flow from the upstream side to the downstream side.

[Overall Configuration of Roving Manufacturing Apparatus 1]
First, the overall configuration of a roving manufacturing apparatus 1 equipped with a splicing device 5 embodying the present invention will be described with reference to FIG.
A roving manufacturing apparatus 1 according to the present embodiment is an apparatus for manufacturing a roving 100 by arranging a plurality of glass fiber bundles (hereinafter referred to as "strands") and winding a thread G formed by joining the fibers into a cylindrical shape.
Specifically, the roving manufacturing apparatus 1 is configured such that the strands 21a, 22a, 23a, and 24a are pulled out from a plurality of (four in this embodiment) cakes 21, 22, 23, and 24 supported by the cake support device 2, and the yarn G obtained by bundling and joining the strands at the first junction X1 is wound around the rotating collet 31 by the winding device 3.
The cakes 21, 22, 23, and 24 are manufactured by bundling several tens to thousands of glass fiber monofilaments with a diameter of 5 μm to 30 μm obtained by spinning molten glass into a glass fiber bundle called a strand, and winding the strand once around a drum. Also, the cakes 21, 22, 23, 24 may be produced by winding a plurality of strands as described in JP-A-6-127970. In this case, a plurality of strands wound around one cake may be pulled out and combined into one strand to form the strands 21a, 22a, 23a, and 24a of the cakes 21, 22, 23, and 24.
In addition, although the number of cakes is four in this embodiment, it may be five or more. When manufacturing rovings with a large count, the number of cakes is preferably 6 to 10.

In this specification, the yarn G may be referred to as a "main line" as appropriate.

The strands 21a, 22a, 23a, and 24a are inspected for thread breakage by a plurality of (four in this embodiment) infrared sensors 41, 42, 43, and 44, respectively.
Here, "thread breakage" includes a blank state when the strands are used up and switched to a new cake, and a state in which the strands pulled out from the cake are cut.

On the other hand, in addition to the plurality of cakes 21, 22, 23, and 24, the cake support device 2 is provided with a cake 25 around which strands 25a for preliminary splicing (hereinafter referred to as "preliminary strands 25a") are wound.

The spare strand 25a pulled out from the spare cake 25 is put on standby in the splicing device 1 through the first junction X1.
Further, the preliminary strand 25a is monitored by the infrared sensor 45, like the plurality of strands 21a, 22a, 23a, and 24a described above.
The reason why the spare strand 25a is passed through the first junction X1 is that after splicing, the spare strand 25a is used as a normal strand forming the main line.

Here, for example, when the strand 21a pulled out from the cake 21 is cut, the number of strands constituting the yarn G is reduced from four to three, so the yarn G becomes thinner.
The portion in this state is referred to as a "reduced diameter portion R" (see FIG. 3(b)).

When the diameter-reduced portion R is generated in the yarn G, yarn splicing is performed in the yarn splicing device 5 in order to restore the diameter-reduced portion R to its original state.
For example, when the infrared sensor 41 detects that the strand 21a has been cut, the splicing strand 25a pulled out from the preliminary cake 25 is entwined with the yarn G.
As a result, the number of strands constituting the yarn G is increased from three to four, so that the diameter-reduced portion R generated in the yarn G is restored to its original state.
Details of the piecing device 5 will be described later.

The spare strand 25a used for splicing will form the main line as a normal strand thereafter, and the cake 21 supplied with the cut strand 21a will be used as a spare cake.

[Configuration of splicing device 5]
Next, the configuration of the piecing device 5 embodying the present invention will be described with reference to FIGS. 1 and 2. FIG.
As shown in FIG. 1, the piecing device 5 mainly includes a first member 51, a second member 52, a gas injection section 53, and the like.
The first member 51 supports the running of the yarn G to be spliced when performing splicing.
Here, "to support the running of the yarn G" means to support the yarn G to run smoothly on the first member 51, and does not only mean that the yarn G directly contacts and supports the first member 51.

The second member 52 is arranged, for example, above the first member 51, is configured to be vertically movable (liftable) relative to the first member 51, and forms a splicing space S (see FIG. 2(b)) for splicing the yarn G by being close to the first member 51. Therefore, the first member 51 and the second member 52 form a splicing space forming portion.
In this embodiment, the second member 52 forms the splicing space S by contacting the first member 51 .

Specifically, when there is no yarn breakage in the plurality of strands 21a, 22a, 23a, and 24a that make up the yarn G, and there is no need to perform yarn splicing, the second member 52 is on standby at a position separated by a certain distance above the first member 51.
On the other hand, if any one of the plurality of strands 21a, 22a, 23a, and 24a forming the yarn G breaks and needs to be spliced, the second member 52 descends (moves relative to the first member 51) and comes into contact with the first member 51, forming a cylindrical splicing space S between itself and the first member 51.

Therefore, as shown in FIG. 2(b), the upper surface of the first member 51 is formed with a lower concave surface 51a forming the lower area of the inner wall surface forming the splicing space S, and the lower surface of the second member 52 is formed with an upper concave surface 52a forming the upper area of the inner wall surface forming the splicing space S.

As shown in FIG. 2A, a guide 52b is provided at the downstream end of the second member 52 in the running direction of the yarn G (the direction of the arrow A) to guide the preliminary strand 25a to pass through a predetermined yarn path.
The guide 52b is formed with a through-hole 52b1 penetrating in the vertical direction. By passing the preliminary strand 25a through the through-hole 52b1, the yarn path of the preliminary strand 25a protruding from the splicing space S on the downstream side in the running direction (hereinafter referred to as the "surplus area Y1") is guided upward.

As shown in FIG. 1, a gripping portion 54 for gripping the vicinity of the tip of the preliminary strand 25a is provided at a distant position on the upper side of the second member 52, and the preliminary strand 25a passes through the upper concave surface 52a (see FIG. 2A) of the second member 52 and the guide 52b in order, and then is gripped by the gripping portion 54 in the surplus region Y1 described above.
In this manner, the preliminary strand 25a for splicing is gripped in advance by the second member 52 so as to protrude from the splicing space S to the downstream side in the running direction of the yarn G when the splicing space S is formed. The gripping portion 54 may be positioned upstream of the splicing space forming portion 52 in the running direction.

The gripping portion 54 includes, for example, a pulley 54a that suspends the surplus region Y1 of the spare strand 25a, and a fastener 54b that temporarily holds the surplus region Y1 of the spare strand 25a suspended on the pulley 54a.

Here, the ring magnet is composed of a plurality of magnets, and since the magnetic force can be adjusted by changing the number of laminated magnets, the gripping force can be easily changed.
Therefore, if a ring magnet is used, the gripping force of the gripping portion 54 can be adjusted within a preferable range of 0.1 to 1.1 gf/mm ² .
If the gripping force is 0.1 gf/mm ² or more, the preliminary strand 25a will not come off from the gripping portion 54.
Further, if the gripping force is 1.1 gf/mm ² or less, the movement of the spare strand 25a during piecing is not hindered, so that piecing can be performed more reliably.

The gas injection section 53 injects gas into the yarn splicing space S in a state where the yarn splicing space S is formed between the first member 51 and the second member 52 .
The gas injection part 53 can be provided on either the first member 51 or the second member 52, for example, and is provided on the first member 51 in this embodiment.

A gas supply source 55 for injecting a flow of gas such as air or nitrogen gas is connected to the gas injection unit 53 .
Then, when the second member 52 moves (lowers) and comes into contact with the first member 51 to form the splicing space S, gas is supplied from the gas supply source 55 and injected into the splicing space S through the gas injection part 53.

As shown in FIG. 2A, the gas injection section 53 is provided on the upstream side of the first member 51 in the running direction of the yarn G (the direction of the arrow A).
As shown in FIG. 2(b), the gas injection section 53 includes an injection pipe 53a through which the gas supplied from the gas supply source 55 passes, and an injection port 53b formed in the inner wall surface of the splicing space S (more specifically, the lower concave surface 51a of the first member 51) for injecting the gas into the splicing space S.

Then, the gas injected from the injection port 53b at the time of splicing becomes a swirl flow Z that spirals from the upstream side toward the downstream side in the running direction of the yarn G along the inner wall surface of the splicing space S (the lower concave surface 51a of the first member 51 and the upper concave surface 52a of the second member 52).

The swirl flow Z caused by the gas injected from the injection port 53b acts indirectly on the yarn G. As shown in FIG.

When the yarn G indirectly receives the swirl flow Z caused by the gas, the yarn G rides on the swirl flow Z in the splicing space S and spirally swirls.
As a result, the spare strand 25a is entwined with the yarn G in a region located within the splicing space S (hereinafter referred to as "splicing work region Y2" as appropriate).

As a result, the surplus region Y1 of the preliminary strand 25a is dragged by the traveling movement of the yarn G and separated from the gripping part 54, and slips through the through-hole 52b1 of the guide 52b, further entangling the intertwined part of the yarn G and the preliminary strand 25a, thereby efficiently and reliably joining the yarn.
Since the preliminary strand 52a is guided by the guide 52b, the preliminary strand 52a that has passed through the through hole 52b1 of the guide 52b is further entangled with the yarn G that has passed through the splicing space S.

The swirling flow Z caused by the gas jetted from the injection port 53b also directly acts on the preliminary strand 25a, and the splicing preliminary strand 25a loosened by the swirling flow Z becomes entangled with the yarn G.
In the present embodiment, the injection port 53b of the gas injection portion 53 is provided in the circumferential direction of the wall surface of the splicing space S so that the gas injected from the injection port 53b directly acts on the preliminary strand 25a. Two injection ports 53b of the gas injection part 53 may be provided so that the gas injected from the ports 53b acts directly.

As described above, in the splicing device 5 of the present embodiment, when the splicing space S is formed, the preliminary strand 25a for splicing is held in advance by the second member 52 so as to protrude from the splicing space S to the downstream side in the traveling direction of the yarn G. After the first member 51 and the second member 52 are brought into contact with each other to form the splicing space S, gas is injected into the splicing space S by the gas injection section 53 to inject the preliminary strand into the yarn G. 25a are intertwined to perform yarn splicing.

[Preliminary Strand 25a in Surplus Region Y1]
Here, if the length of the surplus region Y1 of the preliminary strand 25a is not sufficiently secured, it is difficult to efficiently entangle the yarn G with the preliminary strand 25a.
For example, in the case of a roving with a large count, compared to a roving with a small count, the rigidity of the yarn G is high at normal production speeds, so even when the yarn G spirals, it is difficult to achieve a good entwined state, which may reduce the success rate of splicing and lower the tensile strength of the spliced portion. In particular, when the count of the yarn G is 2000 to 4000 tex, or when the average diameter of one glass fiber monofilament constituting the yarn G is 15 to 30 μm, such problems are conspicuous.

For this reason, in the splicing device 5 of the present embodiment, the length of the yarn G in the splicing space S in the running direction is L1, and the length of the spare strand 25a on the downstream side in the running direction protruding from the splicing space S, that is, the length of the surplus region Y1 is L2, and the length of the spare strand 25a is set so that (L2/L1)>3.

With such a configuration, the length of the surplus region Y1 of the preliminary strand 25a is sufficiently ensured, and even if the preliminary strand 25a is not sufficiently entangled with the yarn G as in the case of the roving with a large count as described above, the surplus region Y1 of the preliminary strand 25a is further wrapped around the mutually entangled preliminary strand 25a and yarn G so as to cover them.

As a result, the portion where the yarn G and the spare strand 25a are intertwined (hereinafter referred to as the “spliced portion 101” (see FIG. 5) as appropriate) is small in volume and tightly intertwined with each other. While realizing a spliced portion in a good entangled state, the success rate of splicing is improved, the tensile strength is improved, and the quality of the roving 100, which is the final product, can be improved.

If the ratio (L2/L1) between the length L1 of the yarn G in the splicing space S in the running direction and the length L2 of the surplus region Y1 of the preliminary strand 25a is too small, it will be difficult for the surplus region Y1 of the preliminary strand 25a to sufficiently wrap around the intertwined preliminary strand 25a and yarn G.
For this reason, it is more preferable that the ratio (L2/L1) is (L2/L1)>8.

If the ratio (L2/L1) between the length L1 of the yarn G in the splicing space S in the running direction and the length L2 of the surplus region Y1 of the spare strand 25a is too large, the surplus region Y1 of the spare strand 25a wraps around the intertwined spare strand 25a and the yarn G too much, and the spliced portion may become too thick.
For this reason, the ratio (L2/L1) is preferably (L2/L1)<50.

In the splicing device 5 of the present embodiment, a guide 52b is provided at the downstream end of the second member 52 in the running direction (direction of arrow A) of the yarn G. The guide 52b guides the yarn path of the surplus region Y1, which is the area of the spare strand 25a protruding from the splicing space S, so that it passes through a predetermined yarn path at the downstream end of the splicing space S in the running direction.

With such a configuration, when the spare strand 25a and the thread G, which are entangled with each other, are wrapped around the surplus region Y1 of the spare strand 25a so as to cover the surplus region Y1, the surplus region Y1 is gradually pulled out from the through hole 52b1 of the guide 52b.
In other words, the surplus region Y1 of the preliminary strand 25a is supported by the guide 52b and is wound around the mutually entangled preliminary strand 25a and the yarn G, thereby suppressing movements other than spirally turning the mutually entangled preliminary strand 25a and the yarn G, making it possible to more reliably helically turn and improve the success rate of splicing.

[Yarn G in splicing space S]
When the flow velocity of the gas injected from the gas injection part 53 is constant, the smaller the cross-sectional area Sa of the splicing space S, the more the swirling flow Z rotates.
On the other hand, if the cross-sectional area Sa of the splicing space S becomes too small, the proportion of the yarn G in the splicing space S becomes too large, and even if the number of rotations of the swirling flow Z increases, the yarn G does not spirally rotate, and it becomes difficult to entwine the yarn G with the splicing work area Y2 of the preliminary strand 25a.

For this reason, in the yarn splicing device 5 of the present embodiment, the shape of the yarn splicing space S is set such that the ratio (Sg/Sa) of the cross-sectional area Sa of the yarn splicing space S to the cross-sectional area Sg of the yarn G is 0.02<(Sg/Sa)<0.20, preferably 0.05<(Sg/Sa)<0.15. It rotates spirally and is entwined with the splicing work area Y2 of the spare strand 25a.

[Operating procedure of splicing device 5]
Next, an operation procedure for performing yarn splicing using the splicing device 5 will be described with reference to FIGS. 3 and 4. FIG.
FIG. 3(a) is a diagram showing a stage in which none of the strands of the plurality of strands 21a, 22a, 23a, and 24a (see FIG. 1) constituting the yarn G is broken, and shows a normal state in which splicing is not required.
In this state, the second member 52, the gas injection section 53, and the grip section 54 are in a standby state.

Here, the normal yarn G forming the main line passes through the support portion 51 and runs toward the winding device 3 (see FIG. 1).
On the other hand, the spare strand 25a for splicing passes through the lower part of the second member 52 and through the through hole 52b1 of the guide 52b, and is suspended over the pulley 54a of the gripping portion 54 located above the second member 52, and is held by the fastener 54b with a gripping force sufficient to prevent the spare strand 25a from falling off.

The second member 52 is on standby separated from the first member 51, and the supply of gas from the gas supply source 55 to the gas injection section 53 is stopped.

FIG. 3(b) is a diagram showing a stage in which at least one of the plurality of strands 21a, 22a, 23a, and 24a forming the yarn G is broken, and shows a state in which the yarn G has a reduced diameter portion R.

When at least one strand among the plurality of strands 21a, 22a, 23a, and 24a is broken, the number of strands constituting the main line is reduced, and a diameter-reduced portion R where the yarn G is thinned is generated.

Here, as described above, these strands 21a, 22a, 23a, and 24a are provided with infrared sensors 41, 42, 43, and 44 (see FIG. 1) for inspecting the presence or absence of yarn breakage, respectively. When these infrared sensors 41, 42, 43, and 44 detect yarn breakage of each strand, they send a detection signal to a separately provided control device (not shown).

Upon receiving a detection signal from at least one of the infrared sensors 41, 42, 43 and 44, the controller instructs the piecing device 5 to splice.
At the same time, the controller instructs the gas supply source 55 to prepare for supplying gas.

The detection signals from the infrared sensors 41, 42, 43, and 44 can be directly transmitted to each section (that is, the second member 52, the gas supply source 55, etc.) that performs yarn splicing without going through the above-described control device.

FIG. 4(a) is a diagram showing the stage in which the piecing device 5 is operated, and shows a state in which the second member 52 is lowered and is in contact with the first member 51. FIG.
In this state, the splicing of the yarn G and the preliminary strand 25a is performed.

Yarn splicing is performed after a predetermined time has passed since at least one of the infrared sensors 41, 42, 43, and 44 detects yarn breakage.
When the yarn breakage is detected, the second member 52 descends toward the first member 51 at a predetermined timing.

When the second member 52 abuts against the first member 51, a splicing space S is formed between them, and splicing is performed inside the splicing space S. As shown in FIG.
Yarn splicing is performed by the gas injection section 53 provided in the first member 51 .
Specifically, when the splicing space S is formed, gas is supplied from the gas supply source 55 to the gas injection section 53 , and the gas is injected into the splicing space S from the gas injection section 53 .

The gas injected into the splicing space S turns into a swirling flow Z (see FIG. 2A) along the inner wall of the splicing space S, and is sprayed onto the preliminary strand 25a for splicing, which is temporarily fixed to the second member 52 via the grip portion 54.
As a result, the yarn G spirally moves around, and the above-described splicing work area Y2 (see FIG. 2(a)) becomes entangled with the diameter-reduced portion R of the yarn G. As shown in FIG.

Thereafter, the preliminary strand 25a for splicing is continuously pulled out from the preliminary cake 25 as the yarn G travels.
At the same time, the surplus region Y1 of the preliminary strand 25a is also released from the grasping by the grasping portion 54 as the yarn G travels. As shown in FIG. 1, the surplus region Y of the preliminary strand 25a is bent by the guide 52b and faces the upstream side of the yarn G, so that the surplus region Y1 of the preliminary strand 25a winds around the mutually entangled preliminary strand 25a and the yarn G as the yarn G runs.

FIG. 4(b) is a diagram showing a stage where the splicing is completed, and shows a state in which the operation of the splicing device 5 is completed.
The second member 52 rises and moves to its original position.

The spare strand 25a for splicing used for splicing is thereafter used as it is as a normal strand, and is combined with the yarn G at the second junction X2 to form a main line.
The spliced yarn G is then wound into a cylindrical shape by a winding device 3 (see FIG. 1) to form a roving 100 .
After the series of steps shown in FIGS. 3 and 4, a new spare strand is set on the second member 52 and temporarily held by the gripper 54 in preparation for the next splicing.

[Configuration of roving 100]
Next, the configuration of the roving 100 embodying the present invention will be described with reference to FIGS. 4(a) and 5. FIG.
As described above, the roving 100 according to the present embodiment is spliced by the splicing device 5, and includes a yarn G made up of a plurality of strands 21a, 22a, 23a, and 24a (see FIG. 1) aligned in one direction, and a spare strand 25a spliced to the yarn G for splicing. Although the number of strands 21 constituting the thread G is four, it may be five or more. When manufacturing a roving 100 with a large count, the number of strands 21 is preferably 6-10.

The roving 100 is formed with a spliced portion 101 where the yarn G and the preliminary strand 25a are spliced, and the preliminary strand 25a is aligned with a plurality of other strands constituting the yarn G in an upstream region in the direction of the arrow A of the yarn G from the spliced portion 101.

As described above, in the splicing portion 101 of the roving 100, as shown in FIG. 4(a), in the splicing space S formed between the first member 51 and the second member 52, the splicing region Y2 (see FIG. 2(a)) of the preliminary strand 25a is first entwined with the reduced diameter portion R (see FIG. 3(b)) of the yarn G, and then the intertwined preliminary strand 25a and the yarn G are entangled with each other. is formed by further winding the preliminary strand 25a so as to cover the surplus region Y1.

In other words, as shown in FIG. 5, at the spliced portion 101 between the yarn G and the preliminary strand 25a in the roving 100, the preliminary strand 25a has a first glass fiber portion 25a1 that is first entangled with the yarn G, and a second glass fiber portion 25a2 that consists of a surplus region Y1 that wraps around the intertwined portion of the first glass fiber portion 25a1 and the yarn G. The second glass fiber portion 25a2 extends from the downstream end of the yarn G in the direction of arrow A by folding back toward the upstream side in the direction, and winds so as to cover the yarn G and the first glass fiber portion 25a1 at the same time.

Thus, in the roving 100 of the present embodiment spliced by the splicing device 5 described above, the spliced portion 101 between the yarn G and the preliminary strand 25a is provided. Therefore, sufficient tensile strength can be imparted to the spliced portion 101 .

In the roving 100 of the present embodiment, the preliminary strand 25a for splicing is set to be thinner than the normal yarn G forming the main line.
That is, when the outer diameter of the cross-sectional area of the partial yarn G to which the preliminary strand 25 is not spliced is D1, and the outer diameter of the cross-sectional area of the first glass fiber portion 25a1 in the preliminary strand 25a is D2, (D1/D2) is set to be ≧1.
D1 and D2 are equivalent circle diameters, and the cross-sectional area of the yarn G is the total value of the equivalent circle diameters of the plurality of strands 21a, 22a, 23a, and 24a.

With such a configuration, the outer diameter of the preliminary strand 25a intertwined with the yarn G is set so as not to exceed the outer diameter of the yarn G, and the rigidity of the preliminary strand 25a is set so as not to exceed the rigidity of the yarn G.
As a result, for example, at the spliced portion 101, when the preliminary strand 25a is entangled with the yarn G, it is possible to prevent the yarn G from being crushed by the preliminary strand 25a, deforming the cross-sectional area of the entire roving 100, and reducing the tensile strength at the spliced portion 101.

Furthermore, in the roving 100 according to the present embodiment, the number of times of winding when the second glass fiber portion 25a2 winds around the yarn G and the first glass fiber portion 25a1 in the preliminary strand 25a is set to be 3 times or more (rotation of 1080° or more).
Further, when the average value of the outer diameter of the cross section of the spliced portion is D3, and the length of the spliced portion is L4, L4/D3≧15 is set.

With such a configuration, the second glass fiber portion 25a2 of the preliminary strand 25a can be more firmly wound around the region where the first glass fiber portion 25a1 of the preliminary strand 25a is entangled with the yarn G, and sufficient tensile strength can be imparted to the spliced portion 101 formed in the roving 100.
The tensile strength is preferably 10-30N. As a result, it is possible to prevent the spliced portion 101 from being pulled apart.
The tensile strength is defined as the force when the spliced portion 101 is pulled apart by holding both ends of the spliced portion 101 with clamps and pulling one of the clamps.

The count of the roving 100 is preferably 100 tex or more. Such counts can be used for many purposes.
Normally, the higher the count of the roving 100, the lower the tensile strength. However, with such a configuration, the roving 100 having sufficient tensile strength can be obtained.
Also, when the average diameter of one glass fiber monofilament constituting the yarn G is 15 to 30 μm, the count of the roving 100 tends to be small, but with such a configuration, the roving 100 having sufficient tensile strength can be obtained.
The number of the roving 100 is more preferably 2000 to 5000 tex.

The spliced portion of the roving 100 preferably has a count of 100 tex or more, more preferably 1000 tex or more, and even more preferably 2000 tex or more.
The spliced portion of the roving 100 preferably has a count of 20,000 tex or less, more preferably 15,000 tex or less, and even more preferably 10,000 tex or less.
Furthermore, the length L4 of the spliced portion of the roving 100 is preferably 2 cm or longer, more preferably 5 cm or longer, and even more preferably 10 cm or longer.
Also, the length L4 of the spliced portion of the roving 100 is preferably 100 cm or less, more preferably 70 cm or less, and even more preferably 50 cm or less.
Thereby, the roving 100 having sufficient tensile strength is obtained.

[experiment]
Next, experiments conducted to confirm the effectiveness of the present invention will be described.

First, four types of rovings of Examples 1 to 4 were prepared as samples of the embodiment of the present invention, and the spliced portions of these rovings were evaluated for "yarn entanglement state", "success rate of splicing" and "tensile strength".

Here, the "entangled state of the yarn" is to be visually observed. If the state of the spliced portion where the preliminary strand and the yarn are entangled is substantially the same as that of the other areas of the yarn other than the spliced portion, and is in a good entangled state, it is rated as "5". However, if compared to other regions of the yarn, the yarn is approximately the same as the spliced portion, but fluff is partially observed, the condition of the yarn spliced portion is approximately the same as that of the yarn other than the spliced portion, but there is a large amount of fluff, etc., is partially observed. and
As for the "success rate of splicing", the number of successful splicing operations was expressed as a percentage (%) with respect to the number of trial splicing operations. Note that each sample was spliced 100 times or more.
The "tensile strength" was measured by clamping both ends of the spliced portion and pulling one of the clamps, and the tensile strength was defined as the force when the spliced portion was pulled apart.

In Example 1, the ratio (L2/L1) between the running direction length L1 of the yarn in the splicing space S formed in the splicing device 5 and the length L2 of the surplus region in the preliminary strand for splicing is set to 8, and the ratio (L4/D3) of the average value D3 of the cross-sectional outer diameter of the spliced portion to the length L4 of the spliced portion is set to 130.
In addition, by using the guide 52b (see FIG. 1) provided in the splicing space forming portion 52 of the splicing device 5, the surplus area of the spare strand is immediately temporarily held by the gripping portion 54 without restricting the yarn path in the surplus area.
Furthermore, the ratio (Sg/Sa) of the cross-sectional area a of the splicing space S to the cross-sectional area Sg of the yarn is set to 0.13.

As a result, in the roving of Example 1, the "thread entanglement state" was "4", the "yarn splicing success rate" was 90%, and the "tensile strength" was 17N.

In Example 2, the ratio (L2/L1) of the running direction length L1 of the yarn in the splicing space S formed in the splicing device 5 and the length L2 of the surplus region in the preliminary strand for splicing is set to 100, and the ratio (L4/D3) of the average value D3 of the cross-sectional outer diameter of the spliced portion to the length L4 of the spliced portion is set to 130.
Also, the ratio (Sg/Sa) between the cross-sectional area a of the splicing space S and the cross-sectional area Sg of the yarn is set to be 0.13.
As for the yarn path of the surplus area of the preliminary strand, the surplus area is immediately temporarily held by the gripping portion 54 without using the guide 52b, as in the first embodiment described above.

As a result, in the roving of Example 2, the "thread entanglement state" was "3", the "yarn splicing success rate" was 82%, and the "tensile strength" was 16N.

In Example 3, the ratio (L2/L1) between the length L1 of the running direction of the yarn in the splicing space S formed in the splicing device 5 and the length L2 of the surplus region in the preliminary strand for splicing, and the ratio (L4/D3) of the average value D3 of the cross-sectional outer diameter of the spliced portion and the length L4 of the spliced portion were set to be 8 and 130, respectively.
Further, after the guide 52b provided in the splicing space forming portion 52 of the splicing device 5 is used to regulate the yarn path in the surplus area of the spare strand, the surplus area is temporarily held by the gripping portion 54.
Furthermore, the ratio (Sg/Sa) of the cross-sectional area a of the splicing space S to the cross-sectional area Sg of the yarn is set to 0.13.

As a result, the roving of Example 3 had a "thread entanglement state" of "5", a "yarn splicing success rate" of 98%, and a "tensile strength" of 17 N, which were better than the results of Examples 1 and 2 described above.

In Example 4, the ratio (L2/L1) between the length L1 of the yarn in the yarn splicing space S formed in the splicing device 5 in the running direction and the length L2 of the surplus region in the preliminary strand for splicing is set to 5, and the ratio (L4/D3) of the average value D3 of the cross-sectional outer diameter of the spliced portion to the length L4 of the spliced portion is set to 80.
Further, after the guide 52b provided in the splicing space forming portion 52 of the splicing device 5 is used to regulate the yarn path in the surplus area of the spare strand, the surplus area is temporarily held by the gripping portion 54.
Furthermore, the ratio (Sg/Sa) of the cross-sectional area a of the splicing space S to the cross-sectional area Sg of the yarn is set to 0.21.

As a result, the roving of Example 4 had a "thread entanglement state" of "4", a "yarn splicing success rate" of 89%, and a "tensile strength" of 13N.

Next, as a comparison target for Examples 1 to 4, a roving of Comparative Example 1 was prepared, in which yarn splicing was attempted multiple times by the above-described splicing device 5, and the spliced portion of this roving was evaluated for "yarn entanglement state", "success rate of splicing" and "tensile strength".

In Comparative Example 1, the ratio (L2/L1) between the length L1 of the running direction of the yarn in the splicing space S formed in the splicing device 5 and the length L2 of the surplus region in the preliminary strand for splicing was set to 2, and the ratio (L4/D3) of the average value D3 of the cross-sectional outer diameter of the spliced portion to the length L4 of the spliced portion was set to 30.
In addition, by using the guide 52b provided in the splicing space forming part 52 of the splicing device 5, the surplus area of the spare strand is immediately temporarily fixed by the grip part 54 without restricting the yarn path in the surplus area.
Furthermore, the ratio (Sg/Sa) of the cross-sectional area a of the splicing space S to the cross-sectional area Sg of the yarn is set to 0.13.

As a result, in the roving of Comparative Example 1, the "thread entanglement state" was "2", the "yarn splicing success rate" was 40%, and the "tensile strength" was 9 N. Compared to the results of Examples 1 to 4 described above, good results could not be obtained.

[Table 1] shows the evaluation results of Examples 1 to 4 and Comparative Example 1 described above.

Based on the evaluation results of these Examples 1 to 4 and Comparative Example 1 shown in [Table 1], the ratio (L2 / L1) to the length of the thread in the thread succession space S formed in the thread succession device 5, and the length of the surplus area in the spare strand for thread succession (L2 / L1) is (L2 / L1). When it is set to be / L1)> 3, it was confirmed that good results could be obtained about "thread entanglement", "thread succession success rate" and "tensile strength".

Further, it was confirmed that when the guide 52b provided in the splicing space forming part 52 of the splicing device 5 is used to regulate the yarn path in the surplus area of the spare strand and then the surplus area is temporarily held by the gripping part 54, even better results can be obtained with respect to the "thread tangling state" and the "success rate of splicing."

5 Yarn splicing device 21a Strand 22a Strand 23a Strand 24a Strand 25a Spare strand 25a1 First glass fiber portion 25a2 Second glass fiber portion 51 First member (yarn splicing space forming portion)
52 Second member (yarn splicing space forming portion)
53 Gas injection unit 100 Roving G Yarn S Yarn splicing space Y1 Surplus area of preliminary strand

Claims (10)

a splicing space forming section for forming a splicing space for splicing a yarn formed by arranging a plurality of strands;
using a yarn splicing device including a gas injection part for injecting gas into the splicing space,
a preliminary strand for splicing is arranged so as to protrude from the splicing space downstream in the running direction of the yarn;
A yarn splicing method for roving, wherein the preliminary strand is intertwined with the yarn in the yarn splicing space by injecting gas into the yarn splicing space from the gas injection part, and then the preliminary strand arranged so as to protrude downstream from the yarn splicing space in the running direction of the yarn is intertwined with the yarn,
The preliminary strand is arranged such that the length L2 of the preliminary strand protruding from the splicing space with respect to the length L1 in the running direction in the splicing space satisfies (L2/L1)>3.
A splicing method for roving characterized by: The preliminary strand protruding from the splicing space passes through a predetermined yarn path during splicing.
The splicing method for rovings according to claim 1, characterized in that: gripping the vicinity of the tip of the preliminary strand before splicing;
The splicing method for rovings according to claim 1 or 2, characterized in that: gripping the vicinity of the tip of the preliminary strand on the upstream side of the downstream end of the splicing space forming section;
The splicing method for roving according to claim 3, characterized in that: a splicing space forming section for forming a splicing space for splicing a yarn formed by arranging a plurality of strands;
a gas injection section for injecting gas into the splicing space;
A splicing device for a roving made of the yarn, wherein the splicing device performs splicing by intertwining a preliminary strand with the yarn by injecting gas into the splicing space from the gas injection unit,
The preliminary strand has a guide for passing through a predetermined thread path at the time of splicing,
The guide is arranged downstream of the splicing space ,
A splicing device characterized by: a thread consisting of a plurality of strands aligned in one direction;
a spare strand spliced to the yarn;
A roving comprising a splicing portion between the yarn and the preliminary strand,
At the splicing portion between the yarn and the preliminary strand,
The spare strand is
a first glass fiber portion intertwined with the yarn;
a second glass fiber portion that extends from the downstream end of the yarn in the first glass fiber portion by folding back toward the upstream side of the yarn and wraps around the yarn and the first glass fiber portion so as to cover the yarn and the first glass fiber portion at the same time;
A roving characterized by: Let D1 be the outer diameter of the cross section of the portion of the yarn where the preliminary strand is not spliced,
When the outer diameter of the cross section of the first glass fiber portion in the preliminary strand is D2,
(D1/D2)≧1,
A roving according to claim 6 , characterized in that: In the preliminary strand,
The number of times the second glass fiber portion winds around the thread and the first glass fiber portion is 3 or more.
8. A roving according to claim 6 or 7 , characterized in that: In the yarn, when the average value of the outer diameter of the cross section of the spliced portion is D3 and the length of the spliced portion is L4, L4/D3≧15 .
A roving according to any one of claims 6 to 8 , characterized in that: The count is 100tex or more,
The roving according to any one of claims 6 to 9 , characterized in that:

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