Winding spool

Abstract

A bobbin for winding according to one embodiment of the present invention is provided with a cylindrical tube body part and flange parts disposed at both end parts of the tube body part, the bobbin for winding being configured from a resin composition containing a main component resin and glass fibers, the main component resin being a polyamide, a polycarbonate, or a combination thereof, and the glass fibers being glass fibers. The flexural modulus of the resin composition is from 8000 MPa to 18000 MPa (inclusive), and the linear expansion coefficient of the resin composition is from 12 ppm / DEG C to 25 ppm / DEG C (inclusive).

Description

Technical Field

[0001] The present disclosure relates to a bobbin for winding a wire. Background Art

[0002] The winding bobbin is used for conveying the long winding wire, and when the winding wire is used, the winding wire wound on the winding bobbin is unwound for use. And the winding bobbin after the winding wire is drawn out from the winding bobbin is generally recovered and reused.

[0003] Conventionally, for example, a winding bobbin has been proposed in which a winding start end of a wire is locked outside a flange of the winding bobbin, thereby enabling efficient winding of the wire (see Patent Document 1).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2003-321164 Summary of the invention

[0007] A winding bobbin according to one embodiment of the present invention comprises a cylindrical body portion and flange portions arranged at both end portions of the body portion, the winding bobbin being composed of a resin composition, wherein the resin composition contains a main component resin and glass fiber, the main component resin is polyamide, polycarbonate or a combination thereof, the bending modulus of the resin composition is greater than 8000 MPa and less than 18000 MPa, and the linear expansion coefficient of the resin composition is greater than 12 ppm / °C and less than 25 ppm / °C. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 This is a schematic diagram showing a process of winding a wire material around a winding bobbin.

[0009] Figure 2 This is a schematic perspective view showing a winding bobbin according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0010] [Problems to be Solved by the Present Disclosure]

[0011] In the process of manufacturing a wire rod, a winding device for winding the wire rod is generally used. Figure 1The winding device 100 shown is a winding device for winding the wire 25 in a multi-layer arrangement on the winding bobbin 50. The winding bobbin 50 has a barrel portion 51 and flange portions 52 and 53 arranged at both ends of the barrel portion 51. In the winding device 100, first, the rear end wire 28 (the terminal end of the wire 25 to be wound around the winding bobbin 50) is inserted into the starting point fixing portion 55 as a through hole of the flange portion 52 of the winding bobbin 50. Then, while the winding bobbin 50 is rotated, the wire 25 is wound around the barrel portion 51 of the winding bobbin 50 via the arm guide 20. The barrel portion 51 has a bearing portion 54 for attaching to a spindle, wherein the spindle is a member for transmitting the rotational power of a rotating mechanism (not shown) that rotates the winding bobbin 50.

[0012] In the case where the winding has a flat shape, in such a winding device, the wire is arranged from one end side to the other end side in the axial direction and wound on the barrel portion of the rotating winding bobbin. Then, at the position where the flange portion of the winding bobbin is in contact, the wire is raised to the upper layer, and then, the wire is reversed from the raised position to further arrange and wind the wire in the axial direction. By repeating the above operation, the wire is arranged in multiple layers and wound on the winding bobbin.

[0013] Regarding the winding bobbin wound with the above-mentioned wire, in terms of manufacturing efficiency, it is ideal that the state of the wire wound in multiple layers is maintained during transportation and storage. However, depending on the manufacturing environment, the winding bobbin formed by winding the wire overseas in a high temperature environment is sometimes exposed to a low temperature environment in winter after being transported to Japan. In this way, when the temperature difference between the winding bobbin during the winding of the wire and the winding bobbin during transportation and storage after the winding of the wire is large, the wound wire is loose due to the different thermal shrinkage of the winding bobbin and the wire, and it is easy to idle and move in the barrel of the winding bobbin. As a result, the end part of the winding start of the wound wire (hereinafter also referred to as the rear end wire) occurs. The rear end wire flies out from the starting point fixing part of the flange part further to the outside of the flange part, and the winding of the wire at the barrel of the winding bobbin collapses, which may become difficult to use. Here, in more detail, "flying out of the rear end wire" refers to the following phenomenon. Usually, at the beginning of winding onto the winding bobbin, the rear end wire is fixed by being hooked on the starting point fixing portion of the flange portion of the winding bobbin. However, sometimes, as the wire is pulled out of the winding bobbin, the fixed rear end wire becomes loose and stretches out, thereby causing the rear end wire to fly outward from the winding bobbin. This phenomenon is called rear end wire flying out.

[0014] On the other hand, a winding bobbin for conveying a wire generally employs ribs to reinforce the structure, but in order to reduce weight and simplify the manufacturing process, high strength is required without increasing the number of such reinforcement members.

[0015] The object of the present disclosure is to provide a winding bobbin which has high strength and can suppress the flying out of the rear end of the wire and the collapse of the winding of the wire at the barrel portion even under conditions where there is a large temperature change when the wire is wound onto the winding bobbin and when the winding bobbin with the wire wound thereon is transported and stored.

[0016] [Effects of the present disclosure]

[0017] A winding bobbin according to one embodiment of the present invention has high strength and can suppress flying of the rear end of the wire and collapse of the winding of the wire at the barrel portion even under conditions where there is a large temperature change when the wire is wound onto the winding bobbin and when the winding bobbin with the wire wound thereon is transported and stored.

[0018] [Description of Embodiments of the Present Disclosure]

[0019] A winding bobbin according to one embodiment of the present invention comprises a cylindrical body portion and flange portions arranged at both end portions of the body portion, the winding bobbin being composed of a resin composition, wherein the resin composition contains a main component resin and glass fiber, the main component resin is polyamide, polycarbonate or a combination thereof, the bending modulus of the resin composition is greater than 8000 MPa and less than 18000 MPa, and the linear expansion coefficient of the resin composition is greater than 12 ppm / °C and less than 25 ppm / °C.

[0020] The winding bobbin is composed of a resin composition containing a main component resin of polyamide, polycarbonate or a combination thereof and glass fiber, and the bending elastic modulus of the resin composition is 8000MPa or more and 18000MPa or less, so that the winding bobbin can have high strength and can be lightweight. In addition, the linear expansion coefficient of the above-mentioned resin composition is 12ppm / ℃ or more and 25ppm / ℃ or less, which can reduce the difference in thermal shrinkage performance between the winding bobbin and the wire. Therefore, even if the temperature difference between the winding bobbin during winding of the wire and the winding bobbin during transportation and storage after the winding of the wire is large, the loosening of the wound wire can be suppressed. Therefore, even under the condition of large temperature changes when the wire is wound on the winding bobbin and when the winding bobbin with the wire wound is transported and stored, the winding bobbin can suppress the flying out of the rear end of the wire and the collapse of the winding of the wire at the barrel. This makes it easy to cope with temperature changes during transportation and storage of the winding bobbin on which the wire is wound, reduces malfunctions of the winding bobbin, and simplifies quality management.

[0021] Here, "linear expansion coefficient" is the thermal expansion coefficient in the thickness direction of the winding bobbin, and refers to the value calculated based on the measured value at -10°C to 40°C using a measuring device using a laser interferometer method. "Bending modulus" is a value measured in accordance with JIS-K-7171 (2016). "Main component" refers to the component with the highest content among the constituent components, preferably a component with a content of 50% by mass or more.

[0022] Alternatively, the linear expansion coefficient of the resin composition may be 16 ppm / °C or less. By setting the linear expansion coefficient of the resin composition to 16 ppm / °C or less, the difference in heat shrinkage performance between the winding bobbin and the wire can be further reduced. Therefore, even when the temperature changes greatly when the wire is wound on the winding bobbin and when the winding bobbin with the wire wound thereon is transported and stored, the flying out of the rear end of the wire and the winding collapse of the wire at the barrel can be further suppressed.

[0023] The main component resin may contain 50% to 75% by mass. The main component resin contains 50% to 75% by mass, which can further improve the bending modulus and thermal expansion coefficient of the winding bobbin.

[0024] The main component resin may include polyamide, and the polyamide may be polyamide 6, polyamide MXD6, or a combination thereof. When the polyamide is polyamide 6, polyamide MXD6, or a combination thereof, the bending modulus and the thermal expansion coefficient may be further increased.

[0025] The resin composition may have a flexural modulus of 11000 MPa or more. When the resin composition has a flexural modulus of 11000 MPa or more, the mechanical properties of the winding bobbin can be further improved.

[0026] [Details of the embodiments of the present disclosure]

[0027] Hereinafter, a winding bobbin according to an embodiment of the present disclosure will be described in detail with reference to the drawings.

[0028] The winding bobbin is used to wind, for example, a flat winding wire. Figure 2 1 is a schematic perspective view of a winding bobbin according to an embodiment of the present disclosure. Figure 2As shown, the winding bobbin 10 has a cylindrical barrel portion 11 for winding a wire material around the outer circumference, and a pair of disc-shaped flange portions 12 and flange portions 13. The flange portions 12 and flange portions 13 are arranged at both ends of the barrel portion 11 along the central main axis of the barrel portion 11. The barrel portion 11 has a bearing portion 14 for attaching to the main shaft, wherein the main shaft is a component for transmitting the rotational power of the rotating mechanism that rotates the winding bobbin (not shown). The flange portion 12 has a starting point fixing portion 15 as a through hole provided on the circumference of the barrel portion 11, and the end portion of the winding start of the wire material is inserted into the starting point fixing portion 15. The starting point fixing portion 15 can also be provided at an adjacent position on the circumference of the barrel portion 11. In addition, for the purpose of improving strength, the pair of flange portions 12 and flange portions 13 have a plurality of ribs 18 and a plurality of ribs 19. Specifically, the outer peripheral surfaces of the pair of flanges 12 and 13 are provided with a plurality of ribs 19 formed in the circumferential direction and a plurality of ribs 18 extending in the radial direction so as to intersect the plurality of ribs 19 in the circumferential direction.

[0029] The wire to be wound around the winding bobbin 10 may be as follows: Figure 1 The flat wire shown may also be a round wire, but the use of a flat wire will further enhance the effect of the winding bobbin 10. There is no particular limitation on the type of wire, and for example, a coated wire such as an enameled wire made of a single core wire composed of a metal conductor such as copper and coated with an insulating coating by baking can be appropriately used. In addition, the thickness and width of the wire are not particularly limited, and for example, a wire having an average thickness of more than 0.5 mm and less than 5 mm and an average width of more than 1 mm and less than 10 mm can be appropriately wound. Here, in the present disclosure, "average thickness" and "average width" refer to the average values ​​of the values ​​measured at any ten points.

[0030] The resin composition constituting the winding bobbin 10 contains a main component resin and glass fiber. The resin composition may also contain an inorganic filler, an organic filler, or a combination thereof as other fillers other than the glass fiber. Examples of inorganic fillers include silicon dioxide and talc (titanium oxide). Examples of organic fillers include carbon fibers, cellulose fibers, cellulose nanofibers, and carbon nanotubes (CNT: Carbon Nanotube).

[0031] The main component resin is polyamide (PA), polycarbonate (PC) or a combination thereof. When the main component resin is polyamide, polycarbonate or a combination thereof, the strength of the winding bobbin can be improved and the weight can be reduced.

[0032] As the above-mentioned polyamide, for example, polyamide 6 (PA6), polyamide 66 (PA66), polyamide 610 (PA610), polyamide 612 (PA612), polyamide 46 (PA46), polyamide 6T (PA6T), polyamide 6I (PA6I), polyamide 9T (PA9T), polyamide M5T (PAM5T), polyamide 11 (PA11), polyamide 12 (PA12), polyamide MXD6 (PAMXD6), polyamide 6 / 66 copolymer (PA6 / 66 copolymer), polyamide 6 / 12 copolymer (PA6 / 12 copolymer), polyamide 6 / 11 copolymer (PA6 / 11 copolymer) are cited. Regarding these polyamides, a plurality of types can also be mixed and used. As the above-mentioned polyamide, among them, from the viewpoint of making the bending elastic modulus and the thermal expansion coefficient in a good range, preferably polyamide 6, polyamide 66, polyamide 610, polyamide 46, polyamide MXD6 or a combination thereof, more preferably polyamide MXD6. Here, "polyamide 6" is a polyamide whose main component is a constituent unit derived from caprolactam. "Polyamide 66" is a polyamide obtained by polycondensing hexamethylenediamine and adipic acid. "Polyamide 610" is a polyamide obtained by polycondensing hexamethylenediamine and sebacic acid. "Polyamide 46" is a polyamide obtained by polycondensing butanediamine and adipic acid. "Polyamide MXD6" is a polyamide obtained by polycondensing m-xylene diamine and adipic acid. Moreover, these polyamides may also contain constituent units derived from other raw material monomers within a range that does not impair the effect of the present invention (for example, it may be less than 5 mol%, may be less than 3 mol%, or may be less than 1 mol%).

[0033] As the polycarbonate, any of aromatic polycarbonate and aliphatic polycarbonate may be selected, but from the viewpoint of strength, aromatic polycarbonate may be used. As the aromatic polycarbonate, bisphenol A polycarbonate may be used.

[0034] As the lower limit of the content of the main component resin in the above-mentioned resin composition, it can be 50% by mass. As the upper limit of the content of the main component resin in the above-mentioned resin composition, it can be 80% by mass, or it can be 75% by mass. In addition, as the range of the content of the main component resin in the above-mentioned resin composition, it can be more than 50% by mass and less than 80% by mass, or it can be more than 50% by mass and less than 75% by mass. By the content of the above-mentioned main component resin being in the above-mentioned range, the bending elastic modulus and thermal expansion coefficient of the winding bobbin 10 can be further improved.

[0035] The resin composition may contain other resins other than the main component resin as long as the purpose of the present disclosure is not impaired. As other resins, for example, acrylonitrile-butadiene-styrene copolymer (ABS) may be used from the viewpoint of improving flexibility.

[0036] The resin composition includes glass fiber. When the resin composition constituting the winding bobbin 10 includes glass fiber, the strength of the winding bobbin 10 can be improved. Examples of the glass fiber include E glass, ECR glass, AR glass, A glass, S glass, C glass, and D glass specified in JIS-R3410:2006.

[0037] As the lower limit of the content of the glass fiber in the above-mentioned resin composition, it can be 20% by mass, or it can be 25% by mass. As the upper limit of the content of the glass fiber in the above-mentioned resin composition, it can be 50% by mass, or it can be 40% by mass. By the content of the above-mentioned glass fiber being more than 20% by mass, the strength of the winding bobbin 10 can be further improved. By setting the content of the above-mentioned glass fiber to less than 50% by mass, the formability and lightweight of the winding bobbin can be well maintained.

[0038] The lower limit of the bending modulus of the resin composition is 8000 MPa, 10000 MPa, or 11000 MPa. On the other hand, the upper limit of the bending modulus of the resin composition is 18000 MPa, or 17000 MPa. When the bending modulus of the resin composition is less than the lower limit, the mechanical properties such as the strength of the winding bobbin 10 may become insufficient. On the other hand, when the bending modulus of the resin composition exceeds the upper limit, the molding of the resin composition may become difficult. It should be noted that the bending modulus of the resin composition can be adjusted by the type of polyamide or polycarbonate, the content ratio of glass fiber, etc.

[0039] The lower limit of the linear expansion coefficient of the resin composition is 12ppm / ℃, and may be 13ppm / ℃. On the other hand, the upper limit of the linear expansion coefficient of the resin composition is 25ppm / ℃, and may be 23ppm / ℃, 20ppm / ℃, 18ppm / ℃, or 16ppm / ℃. When the linear expansion coefficient of the resin composition is less than 12ppm / ℃, it is difficult to manufacture the winding bobbin 10, and mechanical properties such as strength may be reduced. On the other hand, when the linear expansion coefficient of the resin composition exceeds 25ppm / ℃, when the temperature difference between the winding bobbin during winding of the wire and the winding bobbin during transportation and storage after winding of the wire is large, the wire may be easily extended (the rear end wire flies out) and the winding of the wire in the winding bobbin 10 may collapse. When the linear expansion coefficient of the resin composition is within the above range, the difference in heat shrinkage performance between the winding bobbin 10 and the wire can be further reduced. Therefore, even under the condition that the temperature changes greatly when the wire is wound on the winding bobbin 10 and when the winding bobbin 10 on which the wire is wound is transported and stored, the flying out of the rear end of the wire and the winding collapse of the wire at the barrel portion 11 can be further suppressed. It should be noted that the linear expansion coefficient of the above-mentioned resin composition can be adjusted by the type of polyamide or polycarbonate, the content ratio of glass fiber, etc.

[0040] The lower limit of the density of the resin composition may be 1.40 g / cm 2 , can also be 1.42g / cm 2 On the other hand, the upper limit of the density of the resin composition may be 1.65 g / cm 2 , can also be 1.64g / cm 2 When the density of the resin composition is within the above range, the effect of suppressing the deflection of the flange of the winding bobbin 10 when the winding bobbin 10 is fully wound can be further improved, and the mass of the winding bobbin 10 can be further suppressed.

[0041] The winding bobbin 10 may also contain other resins other than the above-mentioned polyamide or polycarbonate. The upper limit of the content of other resins may be 20% by mass, 10% by mass, or 5% by mass. In addition, the winding bobbin 10 may not substantially contain other resins.

[0042] Furthermore, the winding bobbin 10 may contain additives such as a flame retardant, a flame retardant aid, an antioxidant, a lubricant, a colorant, a reflection imparting agent, a masking agent, a processing stabilizer, and a plasticizer.

[0043] [Method for manufacturing a winding bobbin]

[0044] The winding bobbin is manufactured by a known method. For example, first, a resin composition is injected into the injection port of the mold of each component while internal pressure is applied, and after the injected resin is solidified, the molded product is taken out from the mold, thereby manufacturing each component. Then, the components are assembled to manufacture the winding bobbin. In the above-mentioned assembly process, methods such as bonding, welding, and screw fixing can be used.

[0045] In addition, the method for producing the winding bobbin may further include a step of cross-linking the main component resin of the winding bobbin (cross-linking step).

[0046] The above crosslinking can be performed by irradiating the resin composition with ionizing radiation. As the ionizing radiation, for example, gamma rays, electron beams, X-rays, neutron beams, and high-energy ion beams can be used. In addition, as the lower limit of the irradiation dose of the ionizing radiation, it can be 10 kGy or 30 kGy. On the other hand, as the upper limit of the irradiation dose of the ionizing radiation, it can be 300 kGy or 240 kGy. When the irradiation dose is less than the above lower limit, the crosslinking reaction may not proceed sufficiently. On the contrary, when the irradiation dose exceeds the above upper limit, the decomposition of the main component resin may occur.

[0047] The winding bobbin has high strength and can suppress the flying of the rear end of the wire and the collapse of the winding of the wire at the barrel portion even under conditions where there is a large temperature change when the wire is wound onto the winding bobbin and when the winding bobbin with the wire wound thereon is transported and stored.

[0048] [Example]

[0049] Hereinafter, a winding bobbin according to one aspect of the disclosure will be described in more detail by way of examples, but the disclosure is not limited to the following manufacturing examples.

[0050] [Production of winding bobbins No. 1 to No. 12]

[0051] A resin composition containing a main component resin and glass fiber having the composition shown in Table 1 was prepared. It should be noted that "-" in Table 1 means that the corresponding component was not used.

[0052] Next, using a mold, winding bobbins No. 1 to No. 12 having a shape of a cylindrical body and a pair of flanges are made. The length of the body is set to 280 mm, and the diameter of the body is set to 400 mm. The diameter of the surface of the flange is set to 600 mm, and the thickness of the side is set to 8 mm. In No. 1 and No. 3, the following winding bobbins are used: three ribs formed in the circumferential direction and forty-eight ribs extending in the radial direction are provided on the outer circumferential surface side of the outer surface of the flange. In No. 2 and No. 4 to No. 12, the following winding bobbins are used: three ribs formed in the circumferential direction and twenty-four ribs extending in the radial direction are provided on the outer circumferential surface side of the outer surface of the flange. The average thickness of the ribs is set to 6 mm, and the average height of the ribs is set to 25 mm. In addition, the mass of the winding bobbins No. 1 to No. 12 is shown in Table 1.

[0053] [Linear Expansion Coefficient and Flexural Modulus of Resin Composition]

[0054] First, samples composed of resin compositions No. 1 to No. 12 were prepared, and the linear expansion coefficient was calculated from the measured values ​​at 20°C to 120°C using a measuring device using a laser interferometer method (Laser Thermal Dilatometer LIX-2 of ADVANCE RIKEN Co., Ltd.). In addition, the bending elastic modulus was measured using a bending tester in accordance with JIS-K-7171 (2016). The results are shown in Table 1.

[0055] [Charpy impact value of resin composition]

[0056] The No. 4 V-notch test pieces of JIS-Z3111 (2005) composed of the resin compositions No. 1 to No. 12 were used as Charpy impact test pieces. The impact values ​​of the test pieces were measured at 25° C. by a Charpy impact test in accordance with JIS-Z2242 (2005).

[0057] [Flange deflection when fully rolled]

[0058] The flange deflection [mm] of the winding bobbin composed of the resin composition No. 1 to No. 12 when fully wound was measured according to the following process. First, the bobbin that had been fully placed in an environment of 25°C and 50% humidity was placed in a winding device, and the distance between the flanges of the winding bobbin before the wire was wound was measured. Then, after the wire was wound to a full amount, the distance between the flanges was measured in the state where it was placed in the winding device, and the change in the distance between the flanges was calculated. The results are shown in Table 1.

[0059] [Flyout amount of rear end line]

[0060] The amount of rear end wire flying out of the winding bobbins No. 1 to No. 12 was measured according to the following process [mm]. First, the fully wound winding bobbins that had been fully placed in an environment of 25°C and 50% humidity were placed in a winding device, and the initial length of the rear end wire was measured in this state. Next, the wire was pulled out from the fully wound winding bobbins, and when the pulled out wire reached 1000m, the length of the rear end wire was measured, and the change in the length of the rear end wire was calculated. The results are shown in Table 1.

[0061] [Coiling collapse during low temperature impact]

[0062] The winding collapse [%] of the winding bobbins No. 1 to No. 12 during low-temperature impact was measured according to the following process. First, the winding bobbins with a small amount of wire wound on them were fixed on a conveyor tray that was fully placed in an environment of -30°C, thereby adjusting the temperature of the winding bobbins to the same temperature range of 0°C to 10°C as in a winter environment. Next, the offset state and scattered state of the wire after an impact of 15G was applied from the axial direction of the winding bobbin were confirmed several times, and the occurrence rate of wire offset and scattered was calculated. The results are shown in Table 1.

[0063] [Table 1]

[0064]

[0065] As shown in Table 1, for No. 4 to No. 12, the main component resin is polyamide, polycarbonate or a combination thereof, the bending modulus of the resin composition is 8000 MPa or more and 18000 MPa or less, and the linear expansion coefficient of the resin composition is 12 ppm / °C or more and 25 ppm / °C or less, the bending modulus and Charpy impact value are high, and the amount of flyout of the rear end wire and the winding collapse during low temperature impact are greatly reduced. In addition, for No. 4 to No. 12, although the number of radial ribs is half the number of radial ribs of No. 1 and No. 3, the flange deflection when fully wound is also greatly reduced, and the mass of the winding bobbin is equivalent to that of the winding bobbin of No. 1 and No. 3.

[0066] On the other hand, in the case of No. 1 winding bobbin, whose resin composition does not contain polyamide or polycarbonate and glass fiber, the bending elastic modulus is very low, and the amount of the rear end wire flying out and the winding collapse during low temperature impact are both high values. In the case of No. 2 winding bobbin, whose resin composition contains glass fiber but does not contain polyamide or polycarbonate, the bending elastic modulus is low, and the amount of the rear end wire flying out and the winding collapse during low temperature impact are both high values. In the case of No. 3 winding bobbin, whose resin composition contains polyamide but does not contain glass fiber, the bending elastic modulus is very low, and the amount of the rear end wire flying out and the winding collapse during low temperature impact are both high values. In addition, the flange deflection of No. 1 to No. 3 when fully wound is large, and in particular, the flange deflection of No. 2 when fully wound, whose number of radial ribs is twenty-four, is particularly large, similar to the number of radial ribs of No. 4 to No. 12.

[0067] The above results show that the winding bobbin of the present invention has high strength and can suppress the winding of the wire at the barrel portion of the wire from disintegrating even under conditions where there is a large temperature change when the wire is wound onto the winding bobbin and when the winding bobbin with the wire wound thereon is transported and stored.

[0068] Description of Reference Numerals

[0069] 10, 50: winding bobbin; 11, 51: barrel portion; 12, 13, 52, 53: flange portion; 14, 54: bearing portion; 15, 55: starting point fixing portion; 18: radial ribs; 19: circumferential ribs; 20: arm guide; 25: wire; 28: rear end wire (the end portion of the wire); 100: winding device.

Claims

1. A winding bobbin, comprising a cylindrical body and flanges disposed at both ends of the body, The winding bobbin is composed of a resin composition, wherein: The resin composition contains a main component resin and glass fiber. The main component resin is polyamide, polycarbonate or a combination thereof, The resin composition has a bending elastic modulus of 8000 MPa or more and 18000 MPa or less, The resin composition has a linear expansion coefficient of 12 ppm / °C or more and 25 ppm / °C or less.

2. The winding bobbin according to claim 1, wherein: The linear expansion coefficient of the resin composition is 16 ppm / °C or less.

3. The winding bobbin according to claim 1 or 2, wherein: The content of the main component resin is 50 mass % or more and 75 mass % or less.

4. The winding bobbin according to any one of claims 1 to 3, wherein The main component resin comprises polyamide, The polyamide is polyamide 6, polyamide 66, polyamide 610, polyamide 46, polyamide MXD6 or a combination thereof.

5. The winding bobbin according to any one of claims 1 to 4, wherein The resin composition has a flexural modulus of 11000 MPa or more.

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