JP2002338146A - Heater for fusing thermoplastic resin cord used in coreless wound body manufacturing core unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heater for fusing a thermoplastic resin cord used in a coreless wound body manufacturing core unit suitable for manufacturing a coreless wound body having no tear trouble or winding disorder during usage. SOLUTION: The heater comprises a heating element 533 fixed on an external surface of a leaf 52 of the core unit 1 and an iron part 535 heated to a temperature slightly higher than a melting temperature of the thermoplastic resin cord T by the heating element 533, forming through holes H in the thermoplastic resin cord T at an innermost layer of the wound body R, and at the same time, thermally fusing the through holes together. The iron part 535 is detachably attached to the heating element 533, and its tip is formed sharply.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for a core unit for manufacturing a coreless winding body for manufacturing a coreless winding body formed by winding a thermoplastic resin cord in a coil shape without a winding core. The present invention relates to a heater for welding a thermoplastic resin string.

[0002]

2. Description of the Related Art A conventional wound body is obtained by melting an olefin-based thermoplastic resin such as polypropylene and extruding it into a tape.
It is stretched at a take-up speed higher than the extrusion speed to form a thermoplastic resin string, and then wound around a core such as a paper tube in a coil shape. In a wound body in which a thermoplastic resin string is wound around such a paper tube, the paper tube remains after the thermoplastic resin string of the wound body is used in an automatic packing machine or the like. The paper tube after use is severely damaged and it is difficult to reuse it as a core, and since the paper tube is hardened with a synthetic resin adhesive, it cannot be used as a raw material for recycled paper. , Has been disposed of as it is. Such disposal is a burden on the user of the thermoplastic resin string, and there is a strong demand from the user for a roll formed of only the thermoplastic resin string without a core.

Accordingly, the present applicant has disclosed in Japanese Patent Laid-Open No. 7-3156.
Japanese Patent Publication No. 90 proposes such a winding body having only a thermoplastic resin string without a winding core. The technique described in Japanese Patent Application Laid-Open No. Hei 7-315690 discloses a technique in which a thermoplastic resin string is wound around a substantially central portion of a core composed of a left core and a right core joined at a joining surface, and an end of the thermoplastic resin string. After welding with a trowel on the overlapping part with the part of the thermoplastic resin string wound with
The remaining thermoplastic resin string is wound around the core, and then the left core and the right core are removed to manufacture a winding body without a core.

[0004]

However, in the above-mentioned winding body without a winding core described in Japanese Patent Application Laid-Open No. Hei 7-315690, the end of the thermoplastic resin string and the part of the thermoplastic resin string that is wound once are used. Since a trowel is applied and welded to the overlapping part,
In some cases, there is a problem that the welding strength is too strong. In other words, when the welding strength is too strong, when the winding body is used in the automatic packing machine, it is difficult to remove the welded portion only by the rotation force of the delivery roller of the thermoplastic resin string, and an unreasonable force is applied to the delivery roller and the like. Therefore, there is a problem that the automatic packing machine is damaged. Further, if the welding strength is too strong, there is also a problem that the resin at the welded portion of the resin string is easily torn when the welded portion of the thermoplastic resin string is peeled off during use.
Furthermore, since only the overlapping part of the end of the thermoplastic resin string and the part of the thermoplastic resin string that has been wound is welded,
There is also a problem that, depending on the welded position within the entire width of the winding body, the end of the thermoplastic resin string inside the winding body may cause the winding to collapse.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and has been made in order to manufacture a coreless winding body which is suitable for manufacturing a coreless winding body which is free from tearing trouble and collapse during use. It is an object to provide a thermoplastic resin string fusion heater used for a core unit for use.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, a heater for fusing a thermoplastic resin string used in a core unit for manufacturing a coreless wound body of the present invention has through holes formed at a plurality of locations. A plurality of core pieces disposed around the shaft along the circumferential direction thereof and supported so as to be able to advance and retreat along the radial direction of the shaft, and forming a cylindrical core when advanced along the radial direction. And, between these core pieces and the shaft, a plurality of leaves supported so as to be able to advance and retreat along the radial direction of the shaft, and at least one of the gaps between the core pieces has a thermoplastic resin string. The starting end is provided in a core unit for producing a coreless winding body, which has a cord starting end holding means for holding the core piece at the same time as forming the core. When it is wound in a coil shape in a state where it is supported by the leaf and protrudes from the through hole of the core piece, a through hole is formed in the thermoplastic resin string in the innermost layer of the winding body, and simultaneously the through holes are heated. A heater for fusing a thermoplastic resin string, wherein the heating element is fixed to an outer surface of the leaf, and is heated to a temperature slightly higher than a melting temperature of the thermoplastic resin string by the heating element. A through hole is formed in the thermoplastic resin string in the inner layer, and at the same time, a trowel portion that thermally fuses the through holes to each other is provided. The trowel portion is detachably attached to the heating element.

According to the present invention, since the iron portion is detachably attached to the heating element, the iron portion can be easily replaced. Therefore, preparing a plurality of types of iron parts having an optimal length and thickness according to the thickness and width of the thermoplastic resin string,
These can be appropriately replaced.

[0008] The iron portion may be provided with a plurality of needles whose tips are arranged in the width direction of the thermoplastic resin string at intervals substantially equal to the width dimension of the thermoplastic resin string. In this case, since a plurality of thermoplastic resin strings located at the innermost layer of the winding body can be simultaneously opened and fused, the thermoplastic resin strings can be fused and fixed over a wide range.

[0009] The iron portion may be provided with a plurality of needles whose tips are arranged in the direction in which the thermoplastic resin string is wound. In this case, since the through-hole can be opened along the longitudinal direction (the direction of winding around the core) with the thermoplastic resin string located at the innermost layer of the wound body and fused, the thermoplastic resin string can be spread over a wide area. Can be fused and fixed.

[0010] Further, the iron part may be provided with a plurality of needles whose tips are arranged so as to form a triangle, a polygon, a circle, or an ellipse. In this case, since a plurality of thermoplastic resin strings located at the innermost layer of the winding body can be simultaneously opened and fused, the thermoplastic resin strings can be fused and fixed over a wide range.

The shape of the tip of the iron portion may be a simple column, a column with a rounded end, or a column with a sharp end. Of these, it is preferable to use a sharp column with a sharp tip because a through hole can be smoothly opened in the thermoplastic resin string.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

Here, the thermoplastic resin string used in the present embodiment is made of a polypropylene olefin resin which is stretched about 5 to 15 times and has a remarkably improved tensile strength, and has a width of 10 mm to 10 mm. It has a thickness of about 20 mm and a thickness of about 0.3 mm to 1.2 mm. Any thermoplastic resin may be used as long as the tensile strength is improved by stretching, and may be, for example, polyester or polyamide. Moreover, the core unit for manufacturing a coreless core of the present invention and the coreless core formed by the thermoplastic resin string winding device using the same have a thermoplastic resin string as described above of 1000 m to 40 m.
The coreless wound body has a width of about 100 mm to 250 mm, an inner diameter of 200 mm to 410 mm, an outer diameter of 300 mm to 650 mm, and a weight of about 10 kg to 25 kg.

FIG. 1 is a partially broken perspective view of a core unit for manufacturing a coreless wound body (hereinafter, simply referred to as a core unit). FIG. 2A is a schematic front view of the core unit, and FIG.
FIG. 3A is a schematic sectional view taken along the line BB in FIG.
It is a perspective view showing other embodiments of a thermoplastic resin string fusion heater.

The core unit 1 includes a shaft 10, an air cylinder 20 as a plurality of core piece driving means disposed around the shaft 10 along the circumferential direction thereof, and a through hole 311 extending over a plurality of locations. Are formed, and are supported by the air cylinders 20 so as to be able to advance and retreat along the radial direction of the shaft 10, and four core pieces 310 that form the cylindrical core 30 when advanced along the radial direction.
And a plurality of air cylinders 511 as a plurality of leaf driving means disposed around the shaft 10 along the circumferential direction thereof.
And four leaves 520 supported by these air cylinders 511 so as to be able to advance and retreat along the radial direction of the shaft 10 between the core piece 310 and the shaft 10;
Among the gaps between the core pieces 310, a holding bar 40 as a string starting end holding means for holding the starting end of the thermoplastic resin string T in one gap at the same time that the core piece 310 forms the core 30. Things.

The shaft 10 has an octagonal cross section formed by chamfering four corners of a rectangle, and a through hole 101 through which the drive shaft 60 is inserted extends through the entire length in the axial direction. Has been established. The shaft 10 which becomes like this
Port 102, which communicates with the intake / exhaust pipes 201, 512 of the air cylinder 20 and the air cylinder 511,
104 extends from the outer surface to the through hole 101 at a plurality of locations. Note that these ports 10
2, 104 are ports 601 formed on the drive shaft 60,
602 communicate with each other. In FIG. 1, reference numeral 103 denotes an air sealing packing interposed between the ports 102 and 104.

The air cylinders 20 are arranged in two rows around the shaft 10 as described above at equal intervals along the circumferential direction. That is, two air cylinders 2 are provided on four opposing surfaces of the eight surfaces around the shaft 10.
0 are arranged such that one of them is located closer to the distal end from the axial center of the shaft 10 and the other is closer to the proximal end.
These air cylinders 20 are connected to the port 102 of the shaft 10 via an intake / exhaust pipe 201,
It is driven by an externally provided operating mechanism (not shown). That is, by sending air by the operating mechanism,
The piston 202 extends and exhausts the air, whereby the piston 202 retreats. The number of air cylinders 20 is not limited to the present embodiment, and may be one or three or more.

The core piece 310 serves as a winding core when the thermoplastic resin cord T is wound up. The core piece 310 is supported by the above-described air cylinder 20 and is advanced along the radial direction of the shaft 10 by the air cylinder 20. Cylindrical core 30
Is configured. In the present embodiment, the number is four, but is not limited to this. That is, when the shaft 10 advances in the radial direction, three or five or more cylinders may be used as long as a cylinder that can be a core when winding the thermoplastic resin string T can be configured. In addition, each core piece 310
It is not necessary that all of them have the same size as in the illustrated example, and if they can be formed into a cylinder that can serve as a core when the thermoplastic resin cord T is wound up when the shaft 10 advances in the radial direction of the shaft 10. The sizes may be different from each other. Regardless of the number of the core pieces 310, the core pieces 310 are formed in a circular arc shape having a size such that the gap between the joints between the adjacent core pieces 310 becomes as narrow as possible when the core 30 extends in the radial direction of the shaft 10. Preferably, it is formed. The core piece 310 has strength enough to always maintain a cylindrical shape against the tightening force received from the thermoplastic resin string T during winding of the thermoplastic resin string T, and is a lightweight material that reduces the rotational inertia force. It is preferable that the surface is mirror-finished so that the coreless rolled body R obtained by completing the winding can be easily removed. . Note that, in order to reduce friction with the coreless winding body R when the coreless winding body R is detached, a rough surface having a textured surface or the like may be used instead of the mirror finishing. Core piece 3 that looks like this
Naturally, the length dimension of 10 is set to a dimension longer than the width dimension of the coreless winding body R to be manufactured. Also,
A through hole 311 of each core piece 310 has a thermoplastic resin string fusion heater (hereinafter simply referred to as a fusion heater) 5 described later.
30 to make the surface of the core piece 310 appear and disappear,
It is formed in a long hole shape at a plurality of positions near both end surfaces which abut against the adjacent core piece 310, and these through holes 311 are arranged so that their long axes are along the axial direction of the shaft 10. The core piece 310 as described above is supported by the two air cylinders 20 so as to be able to advance and retreat along the radial direction of the shaft as described above. It is also supported by a guide pin 25 provided so as to be able to appear and disappear in the apparatus 10. The guide pin 25 also functions as a guide for the leaf 520.

The holding bar 40 includes a leg 401 and a holding portion 402. The leg portion 401 is a peripheral surface of the shaft 10 and is provided with the above-described air cylinder 20.
Is not provided, that is, the above-described core piece 3
The shaft 10 protrudes along the radial direction of the shaft 10 at a position corresponding to the joint. The leg portion 401 is formed of a plate having a width substantially equal to the width of the core piece 310 (length in the direction along the axis of the shaft 10), and the core piece 310 extends in the radial direction of the shaft 10. The core 30 has a length substantially equal to the distance to the outer surface of the core 30 when the core 30 is advanced to form the core 30. On the other hand, the holding portion 402
When the 0 is formed, the starting end of the thermoplastic resin string T is sandwiched between the core piece 310 and the edge. This holding part 4
Numeral 02 is provided at the distal end of the leg 401 over the entire length in the width direction, and the outer surface is curved to have a curvature substantially equal to the outer surface of the core 30. The clamping bar 40 thus obtained
In the first embodiment, the leg portion 401 and the holding portion 402 are integrally formed of a metal material such as iron.

Air cylinder 51 as leaf driving means
1 is disposed around the shaft 10 along the circumferential direction thereof. That is, this air cylinder 511 is
As shown in FIGS. 1 and 2B, the core piece 31 described above is used.
It is arranged between the air cylinders 20 for zero. The air cylinder 511 is connected to the port 104 of the shaft 10 via an intake / exhaust pipe 512, and is driven by an externally provided operating mechanism (not shown). That is, the piston 513 is retracted by supplying air by the operation mechanism, and the piston 51 is exhausted by exhausting air.
3 is open. The number of air cylinders 511 is not limited to the present embodiment, and may be one or three or more.

The leaf 520 is for supporting the welding heater 530, and is formed in an arc-shaped cross section having substantially the same curvature as the inner surface of the core piece 310.
It is made of a material such as a metal so as to withstand the heat of the welding heater 530. This is the leaf 520
Is disposed between the core piece 310 and the shaft 10 and is supported by the above-described air cylinder 511 so as to be able to advance and retreat along the radial direction of the shaft 10. Also, leaf 52
Guide holes 521 are respectively formed on the base end side and the distal end side of the “0”, and the pair of guide pins 25 are inserted into the guide holes 521. Further, a coil spring 522 is mounted on the guide pin 25 below the guide hole 521, and the leaf spring 5 is
20 is always urged upward, that is, in the direction toward the core piece 310. The number of the leaves 520 can be changed as appropriate according to the number of the core pieces 310.

The welding heater 530 is provided with the leaf 5 described above.
When the leaf 520 advances along the radial direction of the shaft 10, it protrudes from the through hole 311 of the core piece 310 and is fixed to the outer surface of the winding member R on the outermost surface of the winding R. At the same time as forming the through holes H in the thermoplastic resin string T, the through holes H are thermally fused M to each other (see FIG. 6). Note that this fusion heater 530
Is provided on the outer surface of the leaf 520 instead of the outer surface of FIG.
4 (a) and (c), it may be provided on the inner surface side of the leaf 520.

The welding heater 530 includes an electric heating section 533 as a heating element, and an L-shaped iron section 535 which is detachably attached to the electric heating section 533 with a screw 534. As the electric heating unit 533, the same as the electric heating unit used for the soldering iron is preferably used from the viewpoint of cost reduction and ease of handling, but is not limited thereto. The tip of the trowel portion 535, that is, a portion inserted into the through hole 311 of the core piece 310 is formed in a sharp needle shape. Here, as for the degree of sharpness, for example, for a thermoplastic resin string T having a thickness of about 0.63 mm, as shown in FIG. In addition, a thermoplastic resin string T having a thickness of about 0.5 mm
As shown in FIG. 8 (b), the angle θ of the tip may be set to about 20 °. As described above, by adjusting the angle of the tip according to the thickness of the thermoplastic resin string T, the through hole H can be formed smoothly. The shape of the tip of the iron portion 535 does not have to be a sharp needle as described above,
As shown in FIG. 9 (a), it may be a simple columnar shape, or as shown in FIG. 9 (b), may have a rounded tip.

The welding heater 530 thus configured can be slid in the fixing member 531 along the axial direction of the shaft 10 by loosening the screw 532.
The position can be appropriately adjusted according to the width of the thermoplastic resin string T wound up to zero. Note that the position adjustment can also be performed by allowing the fixing member 531 to slide and be fixed on the leaf 520. As described above, since the iron portion 535 is detachably attached to the electric heating portion 533, the iron portion 535 can be easily replaced. Therefore, it is possible to prepare a plurality of types of iron portions having optimum lengths and thicknesses according to the thickness, width, and the like of the thermoplastic resin string T, and to replace these appropriately.

The power supply to the electric heating unit 533 and its control are performed by a contact brush (not shown) provided on the base end surface (the surface opposite to the surface shown in FIG. 1) of the shaft 10 and the contact brush. This is performed from outside via the connected cable 536.

Further, the welding heater 530 is provided with the leaf 52.
0, two through holes 311 in the core piece 310 near each edge.
It is arranged corresponding to. In the present embodiment, four welding heaters 530 are provided for one leaf 520, and 16 for the core 30 as a whole.

The fusing heater 530 as described above is
At the time of fusion, the temperature is raised to a temperature slightly higher than the melting temperature of the thermoplastic resin string T to be wound.
When projecting from 11, the through-holes H are formed in the thermoplastic resin string T in the innermost layer of the winding body R, and the through-holes H are thermally fused together (see FIG. 6).

The form of the iron portion 535 of the welding heater 530 is not limited to the above-described one, but may be a form as described below.

That is, the iron part 535 shown in FIG.
The three needles 535a are arranged at substantially equal intervals along the axial direction of the iron part 535. In this case, each needle 535a
Are arranged along the axial direction of the shaft 10, and are arranged along the width direction of the thermoplastic resin string T wound around the core 30. Here, it is desirable that the interval between the tips of the needles 535a be approximately equal to the width dimension of the thermoplastic resin string T. By setting to such an interval, a plurality of thermoplastic resin cords T located in the innermost layer of the winding body R can be simultaneously opened and fused with a plurality of thermoplastic resin cords T.
The thermoplastic resin string can be fused and fixed over a wide range. That is, if the interval between the tips of the needles 535a is substantially equal to the width of the thermoplastic resin string T, whatever the positional relationship between each needle 535a and the thermoplastic resin string T, As shown in FIG. 7, a through hole H can be formed in the thermoplastic resin string T adjacent on the core 30 without leakage, and fusion M can be performed. In particular, this means that the overlap dimension on the core 30 tends to be small, and the width dimension is small (for example, 6
(mm width) This is effective for the thermoplastic resin string T. Note that the number of the needles 535a is not limited to the three described above, but may be two.
The number is not particularly limited as long as the number is equal to or more than the number. In addition, it is preferable to prepare a plurality of types of iron portions having a plurality of needles set at intervals according to the width dimension of the thermoplastic resin string T so as to correspond to the thermoplastic resin strings T having various width dimensions. As described above, it can be used after being appropriately replaced.

The iron portion 535 shown in FIG. 3 (b) is formed by arranging three needles 535b in the winding direction of the thermoplastic resin string T, that is, along the circumferential direction of the winding body R. is there. In this case, since the through-holes H can be opened along the longitudinal direction (the direction of winding around the core 30) with respect to the thermoplastic resin string T located at the innermost layer of the winding body R, the thermoplastic resin string T can be thermoplastically bonded. The resin string can be fused and fixed over a wide range. In this case, the interval between the tips of the needles 535b is not particularly limited, but may be an appropriate interval according to the width dimension of the thermoplastic resin string T and the inner diameter dimension of the winding body R.

Further, the iron part 535 shown in FIG.
The needles 535c are arranged so as to form a triangle in plan view. In this case, since the through holes H can be simultaneously opened and fused to a plurality of thermoplastic resin strings T located at the innermost layer of the winding body R, the thermoplastic resin strings T can be fused over a wide range. Can be fixed. The number of the needles 535c is three.
The arrangement is not limited to the book, and the arrangement is not limited to the above-described triangular shape in plan view, and may be arranged, for example, to represent a polygon, a circle, or an ellipse.

Incidentally, even in the form shown in FIG.
With the sharpness of the needles 535a, 535b and 535c, as described above, for example, for a thermoplastic resin string T having a thickness of about 0.63 mm, as shown in FIG. Is preferably about 30 °, and the thickness is about 0.5 °.
As shown in FIG. 8B, the angle θ of the tip of the thermoplastic resin string T of about mm is preferably about 20 °. As described above, by adjusting the angle of the tip according to the thickness of the thermoplastic resin string T, the through hole H can be formed smoothly. The needles 535a, 535b, and 535c do not need to have a sharp needle shape, and may have a simple cylindrical shape or a cylindrical shape with a rounded tip as described above. Further, the needles 535a, 535b, 535
As shown in FIG. 3, c does not need to be all the same shape, and may be different between adjacent ones.

Next, a process of manufacturing a coreless wound body using the above-described core unit will be described with reference to FIGS. FIG. 4A is a partial schematic front view of a state in which the leaf 520 has retreated, FIG. 4B is a schematic sectional view of the XX line, and FIG. 4C is a partial schematic front view of the state in which the leaf 520 has advanced. FIG. 5D is a schematic sectional view taken along line YY of FIG.
FIGS. 4A to 4F are schematic front views of the core 30 for explaining steps.

In the initial state, ie, when the winding of the thermoplastic resin string T is started, as shown in FIGS. 4A and 4B, the air cylinder 511 supporting the leaf 520 of the core unit 1 is used. Air is supplied to the leaf 520
Are pulled down toward the shaft 10 against the elastic force of the coil spring 522. The air is exhausted from the air cylinder 20 that supports the core piece 310, and the core piece 310 is pulled down toward the shaft 10 like the leaf 520.
As a result, a gap is formed between the holding portion 402 of the holding bar 40 and the corresponding edge of the core piece 310 so that the tip of the thermoplastic resin string T can be inserted. At this point, the adjustment of the position of the welding heater 530 and the selection and replacement of the iron part 535 are completed.

Next, the starting end of the thermoplastic resin string T is inserted into the gap between the holding portion 402 of the holding bar 40 and the core piece 310. When this is completed, air is supplied to the air cylinder 20 supporting the core piece 310, and FIG.
As shown in (a), the core piece 310 advances, and the starting end of the thermoplastic resin string T is held by the holding portion 4 of the holding bar 40.
02 and the edge of the core piece 310.

When the clamping of the starting end of the thermoplastic resin string T is completed, the core unit 1 starts rotating in a predetermined direction (counterclockwise in any of the drawings) and at the same time, the support shaft 831 of the traverser 83 extends and retracts. The operation starts, and FIG.
As shown in (b), the thermoplastic resin string T is wound on the core unit 1 in a layered manner. Meanwhile, the heating of the welding heater 530 is started to prepare for the later welding.

When the thermoplastic resin string T has been wound up to a certain thickness, the air supplied to the air cylinder 511 of the leaf 520 is exhausted, and FIG. 4C and FIG.
As shown in FIG. 4C, the leaf 520 advances toward the core piece 310 due to the elastic force of the coil spring 522, and FIG.
As shown in FIG. 5D and FIG. 5C, the tip of the iron portion 535 of the welding heater 530 protrudes from the through hole 311 of the core piece 310. As a result, as shown in FIG. 6, the thermoplastic resin string T overlapping in the innermost layer of the
At the same time as the through holes H are formed in a plurality of layers, the thermoplastic resin strings T are partially thermally fused M in the through holes H by the heat of the iron portion 535. The above heat fusion process is performed while the core unit 1 continues to rotate.

After the completion of the heat fusion, air is supplied to the air cylinder 511 of the leaf 520 while the winding of the thermoplastic resin string T is continued, and the leaf 520 is connected to the coil spring 5.
The core piece 310 is retracted against the elastic force of the core piece 310. Thereby, the iron part 535 is separated from the innermost layer of the winding body R.

Thereafter, the rotation of the core unit 1 and the traversing operation of the thermoplastic resin string T are continued until the thermoplastic resin string T is wound up by a predetermined length.

When the thermoplastic resin string T has been wound up by a predetermined length, the rotation of the core unit 1 is stopped, the thermoplastic resin string T is cut with a cutter (not shown), and the thermoplastic resin string is fused with a welding tool. The end of the string T is fused to the surface of the roll R.
This completes the winding of the winding body R.

Thereafter, air is exhausted from the air cylinder 20 of the core piece 310 while the winding body R is supported by a support mechanism (not shown), and as a result, as shown in FIG.
Since the core 10 is retracted toward the shaft 10 and the coreless winding R is supported only by the support mechanism, the coreless winding R is finally discharged from the core 30 to complete the manufacturing.

In the embodiment described above, the innermost layer is heat-sealed M at the initial stage of winding the thermoplastic resin string T, but the intermediate stage of winding or winding is almost completed. The innermost layer may be heat-sealed M at the final stage, or after the winding is completed and before the discharging is started. In the case where the innermost layer is heat-sealed after the winding is completed, there is no possibility that the heat-sealed portion M may come off due to the inertial force applied to the coreless winding body R when the winding is stopped.

[0043]

According to the present invention, since the iron part is detachably attached to the heating element, the iron part can be easily replaced. Therefore, preparing a plurality of types of iron parts having an optimal length and thickness according to the thickness and width of the thermoplastic resin string,
Since these can be appropriately exchanged, a coreless wound body made of any kind of thermoplastic resin string can be manufactured.

In the case where the tip of the trowel is provided with a plurality of needles having an interval substantially equal to the width of the thermoplastic resin string and arranged in the width direction of the thermoplastic resin string, Since a plurality of thermoplastic resin strings located in the innermost layer of the body can be simultaneously welded by forming through holes, the thermoplastic resin strings can be fused and fixed over a wide range. Therefore, it is possible to manufacture a coreless wound body in which the winding from the innermost layer does not collapse during transportation or loading into the packing machine.

In the case where the tip of the iron portion is provided with a plurality of needles arranged in the direction of winding the thermoplastic resin string, the length of the tip of the thermoplastic resin string positioned on the innermost layer of the wound body is reduced. Since a through-hole can be opened along the direction (winding direction around the core) to perform fusion, the thermoplastic resin string can be fusion-fixed over a wide range. Therefore, it is possible to manufacture a coreless wound body in which the winding from the innermost layer does not collapse during transportation or loading into the packing machine.

When the iron part has a plurality of needles arranged at the tip of a triangular or polygonal shape, or a circle or an ellipse, a plurality of heat sinks located at the innermost layer of the winding body are provided. Since the through-holes can be simultaneously opened and fused to the thermoplastic resin string, the thermoplastic resin string can be fused and fixed over a wide range. Therefore, it is possible to manufacture a coreless wound body in which the winding from the innermost layer does not collapse during transportation or loading into the packing machine.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view showing an embodiment of a core unit in which a thermoplastic resin string fusion heater according to the present invention is used.

2 (a) is a schematic front view of a core unit, and FIG. 2 (b) is a schematic sectional view taken along line BB in FIG. 2 (a).

FIG. 3 is a perspective view showing each embodiment of the iron part.

FIG. 4 (a) is a partial schematic front view of a state in which a leaf 520 is retracted, and FIG. 4 (b) is a schematic sectional view taken along line XX of FIG.
(C) is a partial schematic front view of the state where the leaf 520 has advanced, and (d) is a schematic sectional view taken along the line YY.

FIG. 5 is a schematic front view of a core illustrating a winding step.

FIG. 6 is a partially enlarged cross-sectional view along a circumferential direction of the coreless winding body, showing a fusion state of an innermost layer portion of the coreless winding body by the fusion heater.

FIG. 7 is a partially enlarged cross-sectional view along the axial direction of the coreless winding body, showing a fusion state of an innermost layer portion of the coreless winding body by the fusion heater.

FIG. 8 is a partial front view showing another embodiment of the iron part.

FIG. 9 is a partial front view showing another embodiment of the iron part.

[Explanation of symbols]

 Reference Signs List 1 core unit 10 shaft 101 through hole 30 core 310 core piece 311 through hole 40 pinching bar (string starting end pinching means) 401 leg section 402 pinching section 511 air cylinder 520 leaf 530 fusing heater 533 electric heating section (heating element) 535 iron Part 535a, 535b, 535c Tip R Non-core winding T Thermoplastic resin string H Through hole M Heat fusion

 ────────────────────────────────────────────────── ─── Continued on front page (72) Inventor Satoru Tajika -1 Yoshiwara Kamaya, Negami-cho, Nomi-gun, Ishikawa Prefecture Sekisui Jushi Corporation Ishikawa Plant F-term (reference)

Claims (4)

[Claims] 1. A through-hole is formed at a plurality of locations, is provided around a shaft along a circumferential direction thereof, is supported so as to be able to advance and retreat along a radial direction of the shaft, and extends along the radial direction. A plurality of core pieces forming a cylindrical core when advanced, a plurality of leaves supported between the core pieces and the shaft so as to be able to advance and retreat along a radial direction of the shaft; and The start end of the thermoplastic resin string in at least one of the gaps between the core pieces is provided in a core unit for manufacturing a coreless winding body including a string start end holding means for holding the core piece at the same time as forming the core, When the thermoplastic resin cord is wound in a coil shape without a core by the core unit, the thermoplastic resin in the innermost layer of the winding body is supported by the leaf and protrudes from the through hole of the core piece. What is claimed is: 1. A heater for fusing a thermoplastic resin string, wherein a through-hole is formed in a resin string and the through-holes are thermally fused at the same time, and a heating element fixed to an outer surface of the leaf; It is heated to a temperature slightly higher than the temperature, and comprises an iron portion that forms a through hole in the thermoplastic resin string in the innermost layer of the winding body and simultaneously heat-bonds the through holes to each other. A heater for fusing a thermoplastic resin string used in a core unit for manufacturing a coreless roll, which is freely mounted. 2. The iron part has a plurality of needles whose tips are arranged in the width direction of the thermoplastic resin string at intervals substantially equal to the width dimension of the thermoplastic resin string. 2. A heater for fusing a thermoplastic resin string used in the core unit for producing a coreless wound body according to item 1. 3. The core unit for manufacturing a coreless wound body according to claim 1, wherein the iron portion has a plurality of needles whose tips are arranged in a winding direction of a thermoplastic resin string. The heater used to fuse the thermoplastic resin string. 4. The coreless winding body according to claim 1, wherein the iron portion has a plurality of needles whose tips are arranged so as to form a triangle, a polygon, a circle, or an ellipse. A heater for fusing thermoplastic resin strings used in manufacturing core units.