EP3569744A1

EP3569744A1 - Spun yarn cooler

Info

Publication number: EP3569744A1
Application number: EP18210068.5A
Authority: EP
Inventors: Jumpei Suzuki; Kazuhiro Kawamoto
Original assignee: TMT Machinery Inc
Current assignee: TMT Machinery Inc
Priority date: 2018-05-16
Filing date: 2018-12-04
Publication date: 2019-11-20
Anticipated expiration: 2038-12-04
Also published as: CN110499537A; CN209456620U; CN110499537B; JP2019199659A; EP3569744B1; JP7149100B2

Abstract

In a spun yarn cooler, static electricity generated by contact between filaments and an outlet is restrained so that yarn bring-down is facilitated. In a spun yarn cooler 3 in which a cylindrical space 22 to which cooling wind is supplied is formed to extend in an up-down direction and filaments f which are made of synthetic resin and spun out from a spinning unit run in the cylindrical space 22 and then go out from the cylindrical space 22 thorough a lower outlet 27a, a static electricity suppressor 31 which is provided at a periphery of the outlet 27a, is insulating, and restrains generation of static electricity in the filaments f when the filaments f make contact with the static electricity suppressor 31 is provided.

Description

BACKGROUND OF THE INVENTION

The present invention relates to a spun yarn cooler configured to cool filaments which are spun out from a spinning unit and are made of synthetic resin.
For example, a spun yarn cooler recited in Patent Literature 1 (Japanese Unexamined Patent Publication No. 2017-145525 ) includes a cooling cylinder and a partitioning cylinder in which filaments spun out from a spinning beam and made of synthetic resin run. The filaments are cooled and solidified by cooling wind flowing from the circumferential wall of the cooling cylinder. The cooling cylinder and the partitioning cylinder are housed in a metal box, and the cooled filaments go out of the box through an outlet formed in the lower surface of the box.
In a typical yarn production system, a spinning beam and a spun yarn cooler are provided on the upper floor whereas devices such as a winding device for winding yarns are provided on the lower floor. On this account, when yarn production starts, an operator on the upper floor brings filaments discharged from the outlet of the spun yarn cooler down to the lower floor (hereinafter, this operation will be referred to as yarn bring-down), and another operator on the lower floor receives the filaments and performs yarn threading to the winding device, etc. The upper floor is connected to the lower floor through a duct, and the filaments are brought down through the duct.

SUMMARY OF THE INVENTION

In the yarn bring-down, the operator may grip the filaments discharged from the spun yarn cooler and pull the filaments crosswise. In so doing, the filaments may make contact with the periphery of the outlet. In addition to this, for example, filaments may make contact with the periphery of the outlet when filaments on an inclined plate shown in FIG. 7(a) of Japanese Patent No. 6291049 are gripped and pulled crosswise or when filaments are sucked by a yarn sucking device as shown in FIG. 7(b). Because the box is made of metal, movement of electric charges occurs between the filaments and the outlet when the filaments made of synthetic resin make contact with the outlet, with the result that static electricity is generated in the filaments. Consequently, the filaments may disadvantageously wrap around the spun yarn cooler or the operator or adhere to the inner circumferential surface of the duct connecting the upper floor with the lower floor. When such a problem occurs, the yarn bring-down becomes difficult. Furthermore, the filaments may repel each other and do not converge. In such a case, the operator cannot properly grip the filaments.
In consideration of these problems, an object of a spun yarn cooler of the present invention is to restrain static electricity generated by contact between filaments and an outlet so as to facilitate yarn bring-down.
The present invention relates to a spun yarn cooler in which a cylindrical space to which cooling wind is supplied is formed to extend in an up-down direction and filament which is made of synthetic resin and spun out from a spinning unit runs in the cylindrical space and then goes out from the cylindrical space thorough a lower outlet, the spun yarn cooler comprising a static electricity suppressor which is provided at a periphery of the outlet, is insulating, and restrains generation of static electricity in the filament when the filament makes contact with the static electricity suppressor.
The spun yarn cooler of the present invention is provided with the static electricity suppressor which is provided at a periphery of the outlet, is insulating, and restrains generation of static electricity in the filaments when the filaments make contact with the periphery of the outlet. Movement of electric charges scarcely occurs between the filaments and the static electricity suppressor even when the filament makes contact with the static electricity suppressor. On this account, generation of static electricity in the filament is restrained and the yarn bring-down is easily done, when the yarn bring-down is performed so that the filaments make contact with not the outlet but the static electricity suppressor.
In the present invention, the static electricity suppressor is preferably constituted by an insulator different from the outlet.
For example, the static electricity suppressor may be formed by applying insulating paint onto the outlet. However, in this case, applicable paints are restricted, and the paint may be peeled off due to contact with the filaments. On this account, when the static electricity suppressor is not formed by paint but the insulator which is different from the outlet, the material can be selected from various choices, and an optimal material can be chosen in consideration of various factors.
In the present invention, preferably, the insulator is ring-shaped and is provided along the entire periphery of the outlet.
When the insulator is ring-shaped, contact of the filaments to the insulator is ensured in the yarn bring-down. On this account, the generation of static electricity in the filaments is further effectively restrained.
In the present invention, the inner diameter of the ring-shaped insulator is preferably identical with the diameter of the cylindrical space.
When the inner diameter of the ring-shaped insulator is shorter than the diameter of the cylindrical space, the cylindrical space is narrow, and this may cause an adverse effect to the running of the filaments. Meanwhile, when the inner diameter of the insulator is longer than the diameter of the cylindrical space, the filaments tend to make contact with not the insulator but the outlet. When the inner diameter of the insulator is identical with the diameter of the cylindrical space as described above, contact of the filaments with the insulator is ensured without narrowing the cylindrical space.
In the present invention, at least an inner circumferential side of a lower end portion of the insulator is preferably curved.
With this, because the filaments make contact with the curved part of the insulator, damage on the filaments due to contact with the insulator is restrained.
In the present invention, the insulator is preferably made of ceramic.
Because ceramic excels in abrasion resistance, abrasion of the insulator due to contact with the filaments is restrained when the insulator is made of ceramic.
In the present invention, the insulator is preferably matte finished.
When the insulator is matte finished, fine irregularities are formed on the surface and hence the contact resistance of the filaments is decreased. It is therefore possible to further effectively restrain the static electricity generated by friction.
In the present invention, preferably, the insulator is detachably attached to the outlet.
When the insulator is detachable, replacement can be easily done when, for example, the insulator is worn.
In the present invention, preferably, the spun yarn cooler further includes an extension cylinder for elongating the cylindrical space, which is attachable to the outlet, and when the extension cylinder is attached, the insulator is attached to a lower end portion of the extension cylinder.
The extension cylinder may be attached to the outlet in order to enhance the cooling effect. When the insulator is detachable, the insulator is easily detached from the outlet and attached to the extension cylinder.
In the present invention, preferably, the spun yarn cooler further includes: a cylinder body which allows the cooling wind to flow in the cylinder body through part of a circumferential wall; and a box in which the cylinder body is housed, the insulator being fastened to a lower surface of the box together with the cylinder body.
Because the insulator is fastened together with the cylinder body, the number of components and assembly man-hour are reduced.
In the present invention, preferably, a plurality of filaments are cooled.
When one yarn is produced from plural filaments, each filament is narrow and susceptible to static electricity. Yarn bring-down is therefore difficult. The present invention which makes it possible to restrain generation of static electricity in the filaments is therefore particularly effective.
In the present invention, preferably, the thickness of each of the filaments is equal to or less than 6dtex.
Because a narrow filament is susceptible to static electricity and yarn bring-down is difficult as described above, the present invention is particularly effective.
In the present invention, preferably, the filaments are made of nylon 6 or PET-cation.
The static electricity amount generated due to contact with the outlet is particularly large in filaments which are made of nylon 6 or PET-cation. The present invention which makes it possible to restrain generation of static electricity in the filaments is therefore particularly effective.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross section of a melt spinning device of an embodiment.
FIG. 2 is a cross section taken along a line II-II in FIG. 1.
FIG. 3 is an enlarged view of an outlet and its surroundings of a spun yarn cooler of the embodiment.
FIG. 4 shows a case where an extension cylinder is attached.
FIG. 5 is a chemical formulas of nylon 6 and PET-cation.
FIG. 6 is a table showing results of verification experiments.
FIG. 7 shows a modification of an insulator.
FIG. 8 shows a modification of an insulator.
FIG. 9 is an enlarged view of an outlet and its surroundings of a known spun yarn cooler.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following will describe an embodiment of a melt spinning device to which a spun yarn cooler of the present invention is applied, with reference to figures.

(Melt Spinning Device)

FIG. 1 is a cross section of the melt spinning device of the present embodiment. FIG. 2 is a cross section taken along a line II-II in FIG. 1. The up-down direction, front-rear direction, and left-right direction of the melt spinning device 1 of the present embodiment are defined as shown in FIG. 1 and FIG. 2. The melt spinning device 1 includes a spinning beam 2 (equivalent to a spinning unit of the present invention), a spun yarn cooler 3, and an oil guide 4.
The spinning beam 2 is configured to spin out yarns Y made of synthetic resin. To pack housings 11 of the spinning beam 2, spinning packs 12 are attached, respectively. The spinning packs 12 are staggered to form two lines along the left-right direction. Each spinning pack 12 has, at its lower end portion, a spinneret 13 having nozzles 14. As molten polymer is supplied to the spinning pack 12 from an unillustrated pipe or the like, the spinning pack 12 spins out the supplied molten polymer through the nozzles 14 of the spinneret 13, as filaments f. To put it differently, multi-filament yarns Y each formed of plural filaments f are spun out from of the spinning beam 2 of the present embodiment.
The spun yarn cooler 3 is configured to cool the filaments f which are spun out from the spinning beam 2. The spun yarn cooler 3 is provided below the spinning beam 2. The spun yarn cooler 3 includes a rectangular parallelepiped box 20 and cylinder bodies 21 housed in the box 20. The box 20 and the cylinder bodies 21 are made of metal. Each cylinder body 21 is provided directly below the spinning pack 12 and extends in the up-down direction. In accordance with the arrangement of the spinning packs 12, the cylinder bodies 21 are staggered to form two lines along the left-right direction (see FIG. 2). The internal space of each cylinder body 21 is a cylindrical space 22 extending in the up-down direction, in which the filaments f spun out from the spinning pack 12 run.
The internal space of the box 20 is partitioned into upper and lower spaces by a flow adjustment plate 23 which is provided substantially horizontally. The flow adjustment plate 23 is made of a material having flow adjustment capability such as punching metal. The cylinder body 21 is formed in such a way that a cooling cylinder 24 provided in an upper space of the box 20 (i.e., a space above the flow adjustment plate 23) is continuously connected in the up-down direction with a partitioning cylinder 25 provided in a lower space of the box 20 (i.e., a space below the flow adjustment plate 23). The circumferential wall of the cooling cylinder 24 is made of a material having flow adjustment capability such as punching metal, and hence later-described cooling wind is able to flow into the cooling cylinder 24. Being different from the cooling cylinder 24, the circumferential wall of the partitioning cylinder 25 is made of a material which does not allow cooling wind to pass the same.
In an upper surface 26 and a lower surface 27 of the box 20, openings 26a and 27a each having a diameter substantially identical with the inner diameter of the cylinder body 21 are formed at parts where the cylinder bodies 21 are provided, respectively. Each of the openings 26a and 27a communicates with the cylindrical space 22 in the cylinder body 21. The filaments f spun out from the spinning beam 2 enter the cylindrical space 22 through the opening 26a, and go out from the space through the opening 27a. The opening 27a is therefore equivalent to an outlet of the present invention. Hereinafter, the opening 27a will be referred as an outlet 27a. An insulating unit 30 is provided at the outlet 27a as detailed later.
A connecting portion 28 is formed at a rear part of a lower portion of the box 20. The connecting portion 28 is connected to a duct 29. The duct 29 is connected to an unillustrated cooling wind source. The cooling wind supplied from the cooling wind source flows into the lower space of the box 20 via the duct 29. As indicated by arrows in FIG. 1, the cooling air having entered the lower space of the box 20 is adjusted upward while passing through the flow adjustment plate 23, and flows into the upper space of the box 20. The cooling wind having entered the upper space of the box 20 is adjusted when passing through the circumferential wall of the cooling cylinder cooling cylinder 24, and flows into the cooling cylinder 24. As a result, the filaments f running in the cylindrical space 22 of the cylinder body 21 are cooled by the cooling wind and solidified. In this regard, because the circumferential wall of the partitioning cylinder 25 does not allow the cooling wind to pass therethrough, the cooling wind does not directly flows from the lower space of the box 20 into the partitioning cylinder 25.
The oil guide 4 is configured to apply oil to the yarn Y. The oil guide 4 is provided below the spun yarn cooler 3. The yarn Y having been cooled by the spun yarn cooler 3 comes into contact with the oil guide 4. During this contact, the oil guide 4 discharges oil to the yarn Y so that the oil is applied to the yarn Y. The yarn Y to which the oil has been applied by the oil guide 4 is wound onto a bobbin by an unillustrated winding device provided below the oil guide 4, so that a package is formed.

(Problem of Known Structure)

FIG. 9 is an enlarged view of an outlet 27a and its surroundings of a known spun yarn cooler 103. It should be noted that the components having the same structures as those in the present embodiment are given the same reference numerals. In a typical yarn production system, a spinning beam 2 and a spun yarn cooler 3 are provided on the upper floor whereas devices such as an unillustrated winding device for winding yarns Y are provided on the lower floor. On this account, when production of the yarn Y starts, an operator on the upper floor performs yarn bring-down, i.e., brings filaments Y discharged from the outlet 27a of the spun yarn cooler 103 down to the lower floor, and another operator on the lower floor receives the yarn Y and performs yarn threading to the winding device, etc. The upper floor is connected to the lower floor through a duct, and the filaments f are brought down through the duct.
In the yarn bring-down, the filaments f may be pulled crosswise when the operator cuts unnecessary part of the filaments f discharged from the outlet 27a or when the operator throws the filaments f down to the lower floor. At this stage, as shown in FIG. 9, the filaments f may make contact with the periphery of the outlet 27a in the known spun yarn cooler 103. Because the outlet 27a (box 20) is made of metal, movement of electric charges occurs between the filaments f and the outlet 27a when the filaments f made of synthetic resin make contact with the outlet 27a, with the result that static electricity is generated in the filaments f. Consequently, the filaments f may disadvantageously wrap around the spun yarn cooler 103 or the operator, or adhere to the inner circumferential surface of the duct connecting the upper floor with the lower floor. When such a problem occurs, the yarn bring-down becomes difficult. Furthermore, the filaments f may repel each other and do not converge. In such a case, the operator cannot properly grip the filaments f.

(Insulator)

In the present embodiment, in order to restrain the generation of static electricity in the filaments f in the yarn bring-down, the insulating unit 30 is provided at the periphery of the outlet 27a. FIG. 3 is an enlarged view of the outlet 27a and its surroundings of the spun yarn cooler 3 of the present embodiment. The insulating unit 30 includes an insulator 31 and an attaching member 32. The insulator 31 is a ring-shaped (cylindrical) member which is insulating and made of ceramic. The attaching member 32 is a ring-shaped member which is made of metal. The insulator 31 and the attaching member 32 are integrated by suitable means such as screwing or adhesion, and form the insulating unit 30. The inner diameter of the insulator 31 and the inner diameter of the attaching member 32 are both substantially identical with the diameter of the cylindrical space 22 (i.e., the inner diameter of the cylinder body 21).
The insulating unit 30 is detachably attached to the outlet 27a so that the insulator 31 is on the lower side whereas the attaching member 32 is on the upper side. To be more specific, a flange portion 32a is formed at an upper end portion of the attaching member 32. At a lower end portion of the cylinder body 21 (partitioning cylinder 25) housed in the box 20, a flange portion 25a is formed. The flange portion 32a of the attaching member 32 and the flange portion 25a of the cylinder body 21 are fixed from below to the lower surface 27 of the box 20, by bolts 33. In other words, the insulator 31 is fastened to the lower surface 27 of the box 20 together with the cylinder body 21, via the attaching member 32.
As shown in FIG. 3, when the filaments f discharged from the outlet 27a in yarn bring-down are pulled crosswise, the filaments f make contact with the lower end portion of the insulator 31. Because the insulator 31 is insulating, movement of electric charges scarcely occurs between the filaments f and the insulator 31 even when the filaments f make contact with the insulator 31. On this account, the generation of static electricity in the filaments f in the yarn bring-down is restrained. In the present embodiment, the insulator 31 is matte finished. Because of this, fine irregularities are formed on the surface of the insulator 31 and hence the contact resistance of the filaments f is decreased. It is therefore possible to further effectively restrain the static electricity generated by friction. Furthermore, in order to suppress damage to the filaments f when they make contact with the insulator 31, the lower end portion of the insulator 31 is U-shaped to protrude downward.

(When Extension Cylinder Is Attached)

FIG. 4 is an enlarged view of the outlet 27a and its surroundings in a case where an extension cylinder 35 is attached. In order to improve the effect of cooling the filaments f by the spun yarn cooler 3, the extension cylinder 35 may be attached below the outlet 27a as shown in FIG. 4. The extension cylinder 35 is a cylindrical member having flange portions 35a and 35b at upper and lower end portions, respectively, and is made of a material which does not allow fluid to pass therethrough. As the cylindrical space 22 is elongated by attaching the extension cylinder 35, the filaments f are further effectively cooled by cooling wind.
When the extension cylinder 35 is attached, the bolts 33 are loosened and the insulating unit 30 is detached from the lower surface 27 of the box 20. In place of the insulating unit 30, the upper flange portion 35a of the extension cylinder 35 is fixed to the lower surface 27 of the box 20 by the bolts 33. To the lower flange portion 35b of the extension cylinder 35, the insulating unit 30 is attached by bolts 36. In this way, the insulating unit 30 (insulator 31) of the present embodiment is detachable to both the outlet 27a and the extension cylinder 35.

(Types of Filaments)

Examples of the molten polymer spun out from the spinning beam 2 of the present embodiment include nylon 6 (PA6) having a chemical formula shown in FIG. 5(a) and PET (polyethylene terephthalate)-cation having a chemical formula shown in FIG. 5(b). The inventors of the subject application empirically know that an amount of static electricity is particularly large when the filaments f are made of such a material. The present invention which makes it possible to restrain static electricity generated in the filaments f is therefore particularly effective. Furthermore, the present invention is favorably used when the thickness of each filament f is, for example, 6dtex (decitex) or less. This is because a thin filament f is susceptible to an influence of static electricity. It is noted that the material of the filaments f may be synthetic resin which is neither nylon 6 nor PET-cation, and the thickness of each filament f is not restricted to 6dtex or less.

(Verification Experiments)

Verification experiments were carried out to find how effective the insulator 31 actually was. FIG. 6 is a table showing results of verification experiments. The verification experiments were directed to a case of generation of a multi-filament yarn Y made of PET-cation. This multi-filament yarn Y is formed of 144 filaments f, and is 136dtex in thickness. The thickness of each filament f is about 0.94dtex. In the verification experiments, the static electricity amount of the filaments f and whether or not the yarn bring-down was possible were checked in the following three cases: when a matte-finished insulator 31 was provided, when a polished insulator 31 was provided, and when no insulator 31 was provided.
As shown in FIG. 6, when the matte-finished insulator 31 was provided, as compared to the case where no insulator 31 was provided, the static electricity amount was reduced to about 1/80 to 1/15, and the yarn bring-down was properly done. When the polished insulator 31 was provided, although the reduction of static electricity was not as good as in the case of the matte-finished insulator, the static electricity amount was reduced to about 1/10. Furthermore, while it was difficult to perform the yarn bring-down when no insulator 31 was provided, the yarn bring-down was possible in this case. As such, the experiments prove that significant effects are obtained when the insulator 31 which is insulating is provided at the outlet 27a of the spun yarn cooler 3.

(Effects)

In the present embodiment, a static electricity suppressor (insulator 31) which is provided at the periphery of the outlet 27a of the spun yarn cooler 3 and is insulating is provided in order to restrain the static electricity generated in the filaments f when the filaments f make contact with the static electricity suppressor. Movement of electric charges scarcely occurs between the filaments f and the static electricity suppressor 31 even when the filaments f make contact with the static electricity suppressor 31. On this account, generation of static electricity in the filaments f is restrained and the yarn bring-down is easily done, when the yarn bring-down is performed so that the filaments make contact with not the outlet 27a but the static electricity suppressor 31.
In the present embodiment, the static electricity suppressor is formed by the insulator 31 which is different from the outlet 27a. For example, the static electricity suppressor may be formed by applying insulating paint onto the outlet 27a. However, in this case, applicable paints are restricted, and the paint may be peeled off due to contact with the filaments f. On this account, when the static electricity suppressor is not formed by paint but the insulator 31 which is different from the outlet 27a, the material can be selected from various choices, and an optimal material can be chosen in consideration of various factors.
In the present embodiment, the insulator 31 is ring-shaped and provided along the entire periphery of the outlet 27a. When the insulator 31 is ring-shaped, contact of the filaments to the insulator 31 is ensured in the yarn bring-down. On this account, the generation of static electricity in the filaments f is further effectively restrained.
In the present embodiment, the inner diameter of the ring-shaped insulator 31 is substantially identical with the diameter of the cylindrical space 22. When the inner diameter of the ring-shaped insulator 31 is shorter than the diameter of the cylindrical space 22, the cylindrical space 22 is narrow, and this may cause an adverse effect to the running of the filaments f. Meanwhile, when the inner diameter of the insulator 31 is longer than the diameter of the cylindrical space 22, the filaments f tend to make contact with not the insulator 31 but the outlet 27a. When the inner diameter of the insulator 31 is identical with the diameter of the cylindrical space 22 as described above, contact of the filaments f with the insulator 31 is ensured without narrowing the cylindrical space 22.
In the present embodiment, at least the inner circumferential side of the lower end portion of the insulator 31 is curved. With this, because the filaments f make contact with the curved part of the insulator 31, damage on the filaments f due to contact with the insulator 31 is restrained.
In the present embodiment, the insulator 31 is made of ceramic. Because ceramic excels in abrasion resistance, abrasion of the insulator 31 due to contact with the filaments f is restrained when the insulator 31 is made of ceramic.
In the present embodiment, the insulator 31 is matte finished. When the insulator 31 is matte finished, fine irregularities are formed on the surface and hence the contact resistance of the filaments f is decreased. It is therefore possible to further effectively restrain the static electricity generated by friction.
In the present embodiment, the insulator 31 is detachably attached to the outlet 27a. When the insulator 31 is detachable, replacement can be easily done when, for example, the insulator 31 is worn.
In the present embodiment, the extension cylinder 35 for elongating the cylindrical space 22 is attachable to the outlet 27a. When the extension cylinder 35 is attached, the insulator 31 is attached to the lower end portion of the extension cylinder 35. The extension cylinder 35 may be attached to the outlet 27a in order to enhance the cooling effect. When the insulator 31 is detachable, the insulator 31 is easily detached from the outlet 27a and attached to the extension cylinder 35.
In the present embodiment, the spun yarn cooler 3 includes the cylinder body 21 into which cooling wind is able to flow through part of the circumferential wall and the box 20 in which the cylinder body 21 is housed, and the insulator 31 is fastened to the lower surface 27 of the box 20 together with the cylinder body 21. Because the insulator 31 is fastened together with the cylinder body 21, the number of components and assembly man-hour are reduced.
In the present embodiment, the spun yarn cooler 3 cools the filaments f. When one yarn Y is produced from plural filaments f, each filament f is narrow and susceptible to static electricity. Yarn bring-down is therefore difficult. The present invention which makes it possible to restrain generation of static electricity in the filaments f is therefore particularly effective.
In the present embodiment, the thickness of each filament is equal to or less than 6dtex. Because a narrow filament f is susceptible to static electricity and yarn bring-down is difficult as described above, the present invention is particularly effective.
In the present embodiment, the filaments f are made of nylon 6 or PET-cation. The static electricity amount generated due to contact with the outlet 27a is particularly large in filaments f which are made of nylon 6 or PET-cation. The present invention which makes it possible to restrain generation of static electricity in the filaments f is therefore particularly effective.

(Other Embodiments)

The following will describe modifications of the above-described embodiment.
In the embodiment above, the insulator 31 which is a component different from the outlet 27a is provided as the static electricity suppressor of the present invention. Alternatively, for example, the static electricity suppressor may be formed by applying insulating paint onto the outlet 27a.
In the embodiment above, the insulator 31 is ring-shaped and provided along the entire periphery of the outlet 27a. The insulator 31, however, may not be ring-shaped. FIGs. 7(a) and 7(b) show a modification of the insulator. FIG. 7(b) shows the outlet 27a viewed from below. For example, as shown in FIGs. 7(a) and 7(b), an insulating unit 40 (an insulator 41 and an attaching member 42) of the embodiment above may be provided only at part of the periphery of the outlet 27a. While the insulator 41 is provided along a half of the periphery of the outlet 27a in FIGs. 7(a) and 7(b), the insulator may be provided in a different manner. When the insulator 41 is provided not along the entire periphery but at a part of the periphery, in the yarn bring-down, the filaments f are pulled to the side where the insulator 41 is provided. This causes the filaments f to make contact not with the outlet 27a but with the insulator 41, with the result that generation of static electricity in the filaments f is restrained.
In the embodiment above, the insulator 31 is detachably attached to the outlet 27a through the attaching member 32. Alternatively, as shown in FIG. 8, an insulator 51 may be directly attached to the outlet 27a (the lower surface 27 of the box 20). Alternatively, an insulator may be attached to the outlet 27a in a non-detachable manner (e.g., by using an adhesive).
In the embodiment above, the insulator 31 is made of ceramic. Alternatively, the insulator may be made of an insulating material which is not ceramics.
In the embodiment above, the inner diameter of the insulator 31 is substantially identical with the diameter of the cylindrical space 22. In this regard, the inner diameter of the insulator 31 may be longer than or shorter than the diameter of the cylindrical space 22, to some degree. To be more specific, the inner diameter of the insulator 31 may be longer than or shorter than the diameter of the cylindrical space 22, provided that the difference between the diameters is about 1mm at the maximum.
In the embodiment above, the insulator 31 is cylindrical in shape and has the inner diameter substantially identical with the diameter of the cylindrical space 22. Alternatively, the insulator 31 may be tapered in shape so that the inner diameter of the insulator 31 increases toward the outlet 27a.

Claims

A spun yarn cooler in which a cylindrical space (22) to which cooling wind is supplied is formed to extend in an up-down direction and a filament (f) which is made of synthetic resin and spun out from a spinning unit (2) runs in the cylindrical space (22) and then goes out from the cylindrical space (22) thorough a lower outlet (27a),
the spun yarn cooler comprising a static electricity suppressor (31, 41, 51) which is provided at a periphery of the outlet (27a), is insulating, and restrains generation of static electricity in the filament (f) when the filament (f) makes contact with the static electricity suppressor (31, 41, 51).
The spun yarn cooler according to claim 1, wherein, the static electricity suppressor (31, 41, 51) is constituted by an insulator different from the outlet (27a) .
The spun yarn cooler according to claim 2, wherein, the insulator (31, 41, 51) is ring-shaped and is provided along the entire periphery of the outlet (27a).
The spun yarn cooler according to claim 3, wherein, the inner diameter of the ring-shaped insulator (31, 41, 51) is identical with the diameter of the cylindrical space (22).
The spun yarn cooler according to claim 3 or 4, wherein, at least an inner circumferential side of a lower end portion of the insulator (31, 41, 51) is curved.
The spun yarn cooler according to any one of claims 2 to 5, wherein, the insulator (31, 41, 51) is made of ceramic.
The spun yarn cooler according to any one of claims 2 to 6, wherein, the insulator (31, 41, 51) is matte finished.
The spun yarn cooler according to any one of claims 2 to 7, wherein, the insulator (31, 41, 51) is detachably attached to the outlet (27a).
The spun yarn cooler according to claim 8, further comprising
an extension cylinder (35) for elongating the cylindrical space (22), which is attachable to the outlet (27a),
when the extension cylinder (35) is attached, the insulator (31) being attached to a lower end portion of the extension cylinder (35).
The spun yarn cooler according to claim 9, further comprising:
a cylinder body (21) which allows the cooling wind to flow in the cylinder body (21) through part of a circumferential wall; and

a box (20) in which the cylinder body (21) is housed,

the insulator (31, 41, 51) being fastened to a lower surface (27) of the box (20) together with the cylinder body (21).
The spun yarn cooler according to any one of claims 1 to 10, wherein, a plurality of filaments (f) are cooled.
The spun yarn cooler according to claim 11, wherein, the thickness of each of the filaments (f) is equal to or less than 6dtex.
The spun yarn cooler according to any one of claims 1 to 12, wherein, the filaments (f) are made of nylon 6 or PET-cation.