Spool made of magnesium alloy and fishing reel including same

Abstract

Provided is a fishing reel comprising a magnesium alloy spool having a coating film for imparting corrosion resistance, wherein it is possible to precisely control the size of a gap between a frame and a spool flange.　A film formed by a micro-arc oxidation (MAO) treatment is formed on the surface of a part of the spool, the part including at least the flange.

Description

Magnesium alloy spool and fishing reel including same

[0001] The present invention relates to a magnesium alloy spool and a fishing reel including the same, and more particularly to a magnesium alloy spool having a coating for preventing corrosion and a fishing reel including the same.

[0002] Fishing reels come in three types: spinning reels, dual-bearing reels, and single-bearing reels. In dual-bearing and single-bearing reels, the spool is rotatably supported on the reel body, while in spinning reels, the spool is attached to the reel body so that it can move back and forth. The spools of these fishing reels are made of synthetic resin, aluminum alloy, magnesium alloy, or the like.

[0003] Spools made of synthetic resin can be manufactured inexpensively and are lightweight, but they have a low flexural modulus and require a thick wall to maintain rigidity, making it difficult to achieve a high-quality feel.

[0004] Aluminum alloy spools have a higher flexural modulus than synthetic resins, and tend to have a more luxurious feel with a good texture. However, as a metal, the flexural modulus is not as high, so they still need to be thick to maintain sufficient rigidity, which limits how light they can be made.

[0005] Compared to spools made of these materials, magnesium alloy spools are more rigid and can be made thinner, making them lighter. However, magnesium alloys are prone to corrosion, so this type of spool requires a corrosion-resistant structure.

[0006] To address this issue, magnesium alloy spools are typically coated with a paint such as a urethane resin paint, but this type of paint has low surface hardness, and the fishing line can leave marks on the spool surface.

[0007] In response to this, a spool has been proposed that has, on the surface of a magnesium alloy spool body, an oxide film layer formed by anodic oxidation, a low-hardness base layer formed with a cationic electrodeposition paint mainly composed of polyamine, a low-hardness intermediate layer formed with a urethane resin paint, and a high-hardness surface layer formed with an ultraviolet-curing paint, in that order (Patent Document 1). This type of coating increases the surface hardness while improving adhesion between the coating and the spool.

[0008] JP 2000-14288 A

[0009] However, the spool outer diameter of fishing reels, particularly baitcasting reels, must be precisely controlled to prevent the line from getting into the gap between the frame and the spool flange. Conventional spools with multilayer coatings have generally been unable to address this issue because the coating thickness is large and difficult to precisely control. In light of this issue, the present invention aims to provide a fishing reel with a magnesium alloy spool having a coating that provides corrosion resistance, in which the thickness of the coating can be precisely controlled, and ultimately the size of the gap between the reel frame and the spool flange can be precisely controlled.

[0010] In order to achieve this object, the inventors have investigated various coatings and found that this problem can be solved by forming a coating by micro-arc oxidation (MAO) treatment, which led to the present invention.

[0011] That is, the present invention provides a spool made of a magnesium alloy, characterized in that the spool has a coating formed on its surface by micro-arc oxidation (MAO) treatment. In a preferred embodiment, the coating has a thickness of 15 to 25 μm, and particularly preferably 17 to 23 μm. In another preferred embodiment, the present invention also provides a fishing reel including the above-mentioned spool. In a preferred embodiment, the gap between the reel frame and the spool flange is 0.05 to 0.25 mm.

[0012] The coating formed by micro-arc oxidation (MAO) processing is extremely thin and its thickness can be precisely controlled. This allows for precise control of the spool's outer diameter and the size of the gap between the reel frame and the spool flange, allowing for repeated formation of a gap of a size that prevents the line from entering the gap between the frame and the spool flange. Furthermore, the coating formed by micro-arc oxidation (MAO) processing results in a spool that is non-conductive, highly hard, and has excellent corrosion and scratch resistance. Furthermore, because the spool is made of a magnesium alloy, it can be made into a highly rigid, thin-walled spool, allowing for a lighter reel.

[0013] Figure 1 shows a fishing reel according to one embodiment of the present invention. Figure 2 shows the side plates, reel frame, and spool assembly of the fishing reel according to the embodiment of Figure 1. Figure 3 shows a partial cross-sectional view of the fishing reel according to the embodiment of Figure 1. Figure 4 is an enlarged view showing the structure near the gap between the reel frame and the spool flange in Figure 3. Figure 5 is a partial cross-sectional view schematically showing the coating state of the spool surface in the fishing reel according to this embodiment.

[0014] An embodiment of the present invention will now be described in detail. However, the present invention should not be understood as being limited to the following embodiment. FIG. 1 shows a fishing reel according to one embodiment of the present invention. FIG. 2 shows a side plate, a reel frame, and a spool assembly of the fishing reel according to this embodiment. FIG. 3 shows a partial cross-sectional view of the fishing reel according to this embodiment. FIG. 4 is an enlarged view showing the structure near the gap between the reel frame and the spool flange in FIG. 3. FIG. 5 is a partial cross-sectional view schematically showing the coating state of the spool surface in the fishing reel according to this embodiment. The fishing reel 1 is a dual-bearing reel and a low-profile reel for bait casting. As shown in FIGS. 1 to 3, the fishing reel 1 includes a reel body 2, a handle assembly 3 disposed on the side of the reel body 2, and a spool assembly 4 for winding line rotatably and detachably mounted inside the reel body 2. A star drag 5 for drag adjustment is provided on the reel body 2 side of the handle assembly 3.

[0015] The reel body 2 has a reel frame 6 , side plates 7 attached to both sides of the reel frame 6 , and a front cover 8 that covers the front of the reel frame 6 .

[0016] The spool 4a is a magnesium alloy member obtained by injection molding, for example, by die casting. The spool 4a has a cylindrical bobbin trunk 4a-1 and flanges 4a-2 integrally formed on both sides of the bobbin trunk 4a-1 and protruding outward. The spool 4a is non-rotatably fixed to a spool shaft 4b, which is a rod-shaped member made of, for example, stainless steel or an aluminum alloy, for example, by serration connection, thereby forming the spool assembly 4. This fixing method is not limited to a method using concaves and convexes such as serration connection, and various other fixing methods such as adhesive bonding or insert molding can be used. In another embodiment, the spool assembly 4 includes a spool shaft 4b, a spool 4a, and a sleeve (not shown) interposed therebetween, and the spool 4a is fixed to the spool shaft 4b via the sleeve (not shown). In this spool assembly 4, for example, the spool shaft 4b is made of a stainless steel alloy or the like, and the sleeve (not shown) is made of an aluminum alloy or the like.

[0017] 4 and 5, the spool 4a is made of a magnesium alloy, and a coating 11 is formed by MAO treatment on at least a portion of the spool 4a including the flange portion 4a-2, preferably a portion including at least the flange portion 4a-2 and the inner circumferential side 4c of the bobbin trunk portion 4a-1, and particularly preferably the entire surface. The coating 11 formed by MAO treatment varies depending on the electrolytic compound in the electrolytic bath used to form it, but may be, for example, MgO, MgAl ２ O ４ , MgSiO ３ , Cu ３ MgO ４ , V ２ O ５ , V ２ O ３ , VALO ４The coating 11 is made of oxides such as titanium dioxide and zinc oxide, and completely isolates the coated spool portion from the external environment. Furthermore, the coating 11 is non-conductive and extremely hard. Therefore, the coating 11 can prevent corrosion of the spool 4a for a long period of time, and also provides the spool 4a with excellent scratch resistance and UV weather resistance.

[0018] The coating 11 formed by the MAO treatment is also extremely thin and its thickness can be precisely controlled. Its thickness can typically be 1 μm to 50 μm, preferably 5 μm to approximately 40 μm, more preferably 10 μm to 30 μm, even more preferably 15 μm to 25 μm, and particularly preferably 17 μm to 23 μm. Furthermore, by maintaining constant treatment conditions, the thickness can be controlled typically within a range of ±5 μm, preferably ±3 μm. This allows for precise control of the size of the gap 10 between the reel frame 6 and the spool flange portion 4a-2 (see FIG. 4). For example, the gap 10 can be set to a size that prevents the line from entering the gap 10 while ensuring smooth spool operation. The size of such gap 10 is typically 0.05 mm to 0.25 mm, preferably 0.10 mm to 0.20 mm, and more preferably 0.08 mm to 0.18 mm.

[0019] When the spool assembly 4 is formed by directly bonding the spool 4a to the spool shaft 4b, the spool shaft 4b may be made of, for example, an aluminum alloy or stainless steel alloy, but the spool 4a has a non-conductive coating 11 on its surface. This prevents the formation of a local battery and corrosion when seawater enters the reel. In a preferred embodiment, the spool shaft 4b is made of an anodized aluminum alloy. In this case, the non-conductive coating is formed on the surfaces of both the spool 4a and the spool shaft 4b, ensuring a non-electrical contact between them. In a spool assembly 4 including the spool shaft 4b, the spool 4a, and a sleeve (not shown) interposed therebetween, in which the spool 4a is fixed to the spool shaft 4b via the sleeve (not shown), the spool shaft 4b is made of, for example, a stainless steel alloy, and the sleeve (not shown) is made of an aluminum alloy. Even in this case, the spool 4a has a non-conductive coating 11 on its surface, so even if seawater enters the reel, a local battery will not form between these components and corrosion will not occur. In a preferred embodiment, the sleeve is made of an anodized aluminum alloy, so a local battery will not form between the sleeve and the spool shaft, and corrosion will not occur. In another embodiment, the spool shaft 4b and sleeve (not shown) are also made of a magnesium alloy, and have a coating 11 formed on the surfaces of the spool shaft 4b and sleeve (not shown) by MAO treatment. The coating 11 makes the surfaces of each component completely non-conductive, reliably preventing corrosion.

[0020] The coating 11 formed by the MAO treatment can be formed by immersing the spool, and optionally other components such as the spool shaft 4b and sleeve (not shown), in an electrolytic bath, and then oxidizing the Mg on the surface of the spool by micro-discharge.

[0021] The electrolytic bath is typically an aqueous solution of electrolytic compounds at a concentration of 5% to 30% by weight, preferably 7% to 18% by weight, and more preferably 10% to 15% by weight. Examples of the electrolytic compounds include silicates, hydroxides, fluorides, phosphates, aluminates, and combinations thereof, which are included in the coating-forming compounds. Examples of silicates include sodium silicate (Na ２ SiO ３ ), and an example of an alkali metal hydroxide is sodium hydroxide (NaOH). An example of a fluoride is sodium fluoride (NaF). An example of a phosphate is sodium phosphate (Na ３ P.O. ４ Examples of aluminates include sodium aluminum dioxide (NaAlO ２ ), sodium aluminate tetrahydroxide (Na[Al(OH) ４ Among these, silicates, phosphates, or a combination thereof are preferred.

[0022] Microdischarge is performed by applying a high-voltage current to a spool immersed in an electrolytic bath to generate plasma on the surface of the spool. In this process, the spool immersed in the electrolytic bath functions as one electrode, and the counter electrode is an electrode made of any inert metal immersed in the same electrolytic bath. The counter electrode can be, for example, a stainless steel electrode. A direct or alternating current voltage is applied between the two electrodes. The voltage can typically be about 200 V or higher, preferably about 200 V to about 700 V, more preferably about 300 V to about 600 V, and even more preferably about 400 V to about 550 V. The temperature of the electrolytic bath is not particularly limited, but is typically about 20° C. to about 40° C., preferably about 25° C. to about 35° C. However, temperatures outside these ranges can also be used. The MAO treatment time can be about 5 minutes to 1 hour, preferably 10 to 30 minutes, and more preferably 15 to 25 minutes.

[0023] In a preferred embodiment, the coating 11 formed by the MAO treatment forms the outer surface of the spool without the need for any additional layers. The coating 11 formed by the MAO treatment can have different colors depending on the type of oxide that constitutes it. For example, by forming a coating using the oxides listed above or a combination thereof, a coating with a unique black or white texture can be obtained. The unique color imparted by the coating 11 formed by the MAO treatment can directly form the design of the reel, resulting in a reel with a unique texture.

[0024] The spool of the present invention is made of a magnesium alloy, which provides high rigidity and allows for thinning, resulting in a lighter reel. These characteristics make it ideal for use in low-profile reels, allowing for the design of low-profile reels that can easily cast even extremely lightweight rigs weighing approximately 3g. However, the present invention is not limited to this embodiment and can also be applied to spools of other fishing reels, such as lever-drag and electric dual-bearing reels, spinning reels, and single-bearing reels.

[0025] The present invention will be explained in more detail below with reference to examples, but the present invention is not limited to these examples.

[0026] 1. Manufacturing of spools 120 magnesium alloy spools of the following sizes were manufactured by cutting round bar material and then MAO treatment: Spool flange diameter: 30 mm Spool width: 25.5 mm

[0027] The spool is then cooled to room temperature using sodium silicate (Na ２ SiO ３ ) and sodium phosphate (Na ３ P.O. ４ The MAO treatment was carried out by immersing the sample in an electrolyte solution containing 15 to 20 mass % of each of the above compounds and adjusted to a pH of 9 to 13 under the following conditions: Voltage and current conditions: 10-15 A / dm ２Constant current, 500V-550V voltage Current supply method: DC constant current Frequency: 500Hz Duty ratio: 20% Positive / negative current ratio: 3:1 Anodizing time: 15-25 minutes in a recycling cooling device at 25°C

[0028] After the treatment, the spools were cut and the cut surfaces were observed under an electron microscope to confirm the thickness of the oxide coating formed. The thickness of the coating formed on each of the 120 spools was confirmed to be 20±3 μm.

[0029] 2. UV Weathering Test The spool with the MAO coating obtained above was subjected to a UV weathering test. The test conditions were as follows. (Test Conditions) The test was carried out in accordance with the SAE J1960 standard. Specifically, the spool manufactured as described above was subjected to UV weathering test at 33 KJ / m using "Accelerated Exposure of Automotive Exterior Materials Using Controlled Irradiance Water-Cooled Xenon Arc Apparatus" in the following cycle: ２ to 1000 kJ / m ２ 14 levels of UV intensity (33KJ / m ２ , 66 KJ / m ２ , 100 KJ / m ２ , 233 KJ / m ２ , 300 KJ / m ２ , 366 KJ / m ２ , 500 KJ / m ２ , 600 KJ / m ２ , 700 KJ / m ２ , 800 KJ / m ２ , 833 KJ / m ２ , 933 KJ / m ２ , 966 KJ / m ２ , and 1000 KJ / m ２ ) and exposed to ultraviolet light.

[0030] (Evaluation) The surface of the treated spool was visually inspected for discoloration, cracks, peeling, and blisters. Spools that showed any of these were evaluated as "x", and spools that showed none were evaluated as "good".

[0031] (Test Results) The spools subjected to the tests with different amounts of ultraviolet light were evaluated as follows. Anodized spool: 500KJ / m ２ However, the spool of this example, which had a coating formed by MAO treatment, showed no discoloration, cracking, peeling, or blisters up to 600 KJ, demonstrating superior UV weather resistance.

[0032] 1. Fishing reel 2. Reel body 3. Handle assembly 4. Spool assembly 4a. Spool 4a-1. Bolt trunk 4a-2. Flange 4b. Spool shaft 5. Star drag 6. Reel frame 7. Side plate 8. Front cover 9. Sleeve 10. Gap 11. Coating formed by MAO treatment

Claims

1. A spool made of a magnesium alloy, characterized in that the surface of at least the flange portion has a coating formed by micro-arc oxidation (MAO) treatment.

2. The spool according to claim 1, further comprising a coating formed by micro-arc oxidation (MAO) treatment on the surface of a portion of the spool including the inner circumference of the spool body.

3. A spool as claimed in claim 1 or 2, having a coating formed on the entire surface of the spool by a micro-arc oxidation (MAO) process.

4. A spool according to any one of claims 1 to 3, wherein the coating has a thickness of 20±3 μm.

5. A spool assembly in which the spool according to any one of claims 1 to 4 is attached to a spool shaft directly or via a sleeve.

6. The spool assembly according to claim 5, wherein said spool shaft is constructed of anodized aluminum alloy.

7. A spool assembly comprising the spool according to any one of claims 1 to 4, a spool shaft, and a sleeve interposed therebetween, said spool being attached to the spool shaft via the sleeve.

8. The spool assembly of claim 5, wherein the sleeve and / or the spool shaft are constructed from anodized aluminum alloy.

9. A fishing reel comprising a spool according to any one of claims 1 to 4 or a spool assembly according to any one of claims 5 to 8.

10. The fishing reel according to claim 9, wherein the gap between the reel frame and the flange of the spool is 0.08 mm to 0.18 mm.

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