Fishing rod grip and fishing rod

Abstract

Provided is a fishing rod grip that can be easily processed, has an appropriate hardness, and provides good grippability. The fishing rod grip according to the present invention is provided with a grip core 10A molded from a single material. The grip core 10A is characterized by having a three-layer structure including an intermediate layer 11, and an inner skin layer 12 and an outer skin layer 13 that are provided on both surfaces of the intermediate layer 11 and are harder than the intermediate layer 11.

Description

Fishing rod grip and fishing rod

[0001] CROSS-REFERENCE This application claims priority to Japanese Patent Application No. 2023-186408 (filed October 31, 2023), the contents of which are incorporated herein by reference in their entirety. The present invention relates to a fishing rod grip and a fishing rod having features in the grip portion that is held when actually fishing.

[0002] For example, fishing rods such as tenkara rods are provided with fishing rod grips (hereinafter referred to as "grips") that are held when fishing. Conventional grips are formed by cutting a block of material such as urethane foam to reduce weight.

[0003] Grips with a laminated structure of multiple layers are also known. For example, Patent Document 1 discloses a grip with a three-layer structure in which a thermosetting epoxy resin sheet is disposed on a foam core material and a thermoplastic fiber-reinforced resin layer is disposed on the outer surface of the resin sheet. Furthermore, Patent Document 2 discloses a grip with a three-layer structure consisting of an inner layer, a middle layer, and an outer layer. The middle layer is made of a shock-absorbing material (thermoplastic elastomer), and the inner and outer layers are made of a hard polyurethane resin material.

[0004] Patent No. 6602215 JP 7-96879

[0005] With conventional urethane foam grips, it is difficult to control the expansion ratio, which can lead to variations in hardness within the block material, and depending on the cutting position, the quality of each product can vary. Furthermore, the cutting process can damage the material, resulting in waste. Furthermore, the surface is prone to becoming uneven, which adds time to the subsequent painting process.

[0006] With the three-layer grips described above, it is difficult to select the appropriate hardness for the grip, and depending on the surface roughness, the lead time for grip processing may increase.

[0007] The present invention was made in response to the above-mentioned problems, and aims to provide a fishing rod grip that can be easily processed, has appropriate hardness, and provides a comfortable grip, as well as a fishing rod equipped with such a grip.

[0008] In order to achieve the above-mentioned object, the present invention provides a fishing rod grip that is attached to the base end side of the butt shaft of a fishing rod and is gripped, and the fishing rod grip is characterized in that it has a grip core material molded from a single material, and the grip core material has a three-layer structure including an intermediate layer and inner and outer skin layers that are harder than the intermediate layer and are provided on both sides of the intermediate layer.

[0009] The fishing rod grip with the above-mentioned configuration is molded into a three-layer structure using a single material, eliminating the need to cut blocks of urethane foam or other materials as in the past, and therefore eliminating material waste. Furthermore, by forming hard skin layers on both sides of the middle layer, the amount of plastic deformation is reduced, and even if braiding is applied to the surface side (exposed side), it does not deform, so there is no change in grip feel and no variation in quality between products.

[0010] The above-mentioned fishing rod grip can be attached to the butt shaft of various fishing rods, and is particularly suitable for tenkara rods, where users are particular about the grip configuration. For such fishing rods, a configuration in which multiple rods are joined together is preferable, and the joining structure between the rods can be a telescopic type, a straight joint type, a spigot joint type, etc.

[0011] According to the present invention, it is possible to obtain a fishing rod grip that can be easily processed, has an appropriate hardness, and provides a comfortable grip, and a fishing rod equipped with such a grip.

[0012] 1 is a perspective view showing one embodiment of a fishing rod grip according to the present invention; 2 is a cross-sectional view taken perpendicular to the axial direction of the fishing rod grip shown in FIG. 1; 3(a) shows the cross-sectional view shown in FIG. 2, and 3(b) is an enlarged view of the grip core material shown in FIG. 3(a). 4 is a schematic diagram showing the thermally expandable microcapsules used in the grip core material set in a mold and expanded after heating; 5 is a graph showing the change in displacement when a grip according to the present embodiment (invention product) and a current product are repeatedly pressed 10 times, with 3(a) showing the test results for the invention product and 3(b) showing the test results for the current product; 6 is a table showing specific numerical values ​​of FIGS. 5(a) and 5(b). 7(a) is a graph comparing the maximum displacement of the invention product and the current product for each repeated pressing test, and 7(b) is a graph comparing the amount of plastic deformation of the invention product and the current product for each repeated pressing test. 8 is a table showing sensory evaluations of the invention product and the current product by 10 testers.

[0013] The present invention relates to a grip that is attached to the base end of a butt shaft of a fishing rod and is held by hand, and is characterized in that the grip has a three-layer structure including a grip core material molded from a single material, an intermediate layer, and inner and outer skin layers that are harder than the intermediate layer and are provided on both sides of the intermediate layer. In the embodiment described below, an example will be described in which the grip core material is molded using a mold from a thermally expandable capsule resin to achieve this configuration.

[0014] First, the grip core material constituting the grip according to this embodiment will be described with reference to the schematic diagram in Figure 4. In this embodiment, thermally expandable microcapsules are used as the constituent material of the grip core material. The thermally expandable microcapsules are a particulate foam material made of, for example, an acrylic resin (a copolymer of acrylonitrile, methacrylonitrile, and methyl methacrylate), a vinyl resin (a copolymer of vinylidene chloride and vinyl chloride), or the like.

[0015] This type of microparticle-type foam material is filled directly into a mold (upper and lower molds) with recesses formed to form a desired shape (the outer shape of the grip). When heated, the thermally expandable microcapsules expand. A typical characteristic of thermally expandable microcapsules is that when heated, the outer shell resin softens and expands into a roughly spherical shape. This volumetric expansion occurs in the middle portion away from the upper and lower molds, but in the portion in contact with the mold (the upper and lower mold sides), expansion is suppressed by pressure from the mold. As the microcapsules move toward the surface, they gradually expand from a spherical shape to an elliptical shape. Furthermore, in the region where the microcapsules expand into an elliptical shape, the density of the thermally expandable microcapsules increases, resulting in the formation of a layer (called a skin layer) that is harder than the middle portion.

[0016] In this embodiment, attention is paid to such expansion characteristics, and the grip structure is configured so that, although the material is a single material, a skin layer with high hardness is arranged on the front and back sides, and an intermediate layer with low hardness is arranged in the middle part.

[0017] The grip core material constituting the grip according to this embodiment will be described below with reference to Figures 1 to 3. In these figures, Figure 1 is a perspective view showing one embodiment of the grip, Figure 2 is a cross-sectional view in a direction perpendicular to the axial direction of the fishing rod grip shown in Figure 1, Figure 3(a) shows the state of the cross-sectional view shown in Figure 2, and Figure 3(b) is an enlarged view of the grip core material in Figure 3(a).

[0018] The fishing rod according to this embodiment includes a butt rod 1 and a tip rod (tip rod) that is joined to the tip of the butt rod 1. The tip rod can have a telescopic joint structure, a straight joint structure, a spigot joint structure, or other joint structure.

[0019] The butt rod 1 is formed into a tubular shape by winding a fiber-reinforced resin material (prepreg) made of synthetic resin impregnated with reinforcing fibers. In this case, the rod that constitutes the fishing rod may have a solid structure formed from a superelastic alloy or superelastic resin, or may be formed from a natural material such as bamboo. Furthermore, as long as the fishing rod has a grip that can be held, it may be a boat rod, a casting rod, a reel-equipped fishing rod, etc., and may be formed as a single rod other than one made up of multiple rods joined together.

[0020] A grip 10 is fixed to the base end of the butt rod 1. The grip 10 is configured so that it gradually bulges radially from the axis X as it moves toward the rear end, making it easy to grip.

[0021] The grip core material 10A that constitutes the grip 10 is molded using a mold. The mold is composed of a split mold with a recess corresponding to the external shape of the grip 10 shown in Figure 1, and the recess of this split mold is filled with thermally expandable microcapsules, which are a particulate-type foam material as described above, and heated to form the grip 10. In this case, a core metal is positioned and held within the split mold so that an axial hole 10a is formed in the center. The thermally expandable microcapsules expand due to heating, molding the grip into the desired shape, and then the core is removed.

[0022] The grip 10 molded in this manner is integrated with the butt rod 1 by applying adhesive to the surface of the butt rod 1 and fitting it into the axial hole 10a. The grip 10 molded in this manner may also be subjected to post-treatment such as braiding or painting to make it less slippery or to improve its design.

[0023] As described above, the grip core material 10A is a microparticle-type thermally expandable microcapsule, and when heated, the outer shell resin constituting the capsule softens, the internal gas expands, and the capsule itself expands. Such thermally expandable microcapsules begin to expand when they reach a foaming initiation temperature, and then, as they continue to be heated, their expansion peaks at a maximum foaming temperature (when the maximum foaming temperature is exceeded, they begin to shrink).

[0024] As shown in Fig. 4, when such microparticle-type thermally expandable microcapsules begin to expand due to heating, the region in contact with the mold (surface region) is compressed, suppressing the expansion of each microparticle, and the surface region expands into an ellipsoidal shape, as shown in Fig. 3(b). That is, in the region of the intermediate layer 11, the thermally expandable microcapsules 20 are not compressed by the mold, so they expand into a substantially spherical shape, while the thermally expandable microcapsules 20' in the surface region (inner skin layer 12, outer skin layer 13) swell into an ellipsoidal shape, resulting in a higher density (the density of the thermally expandable microcapsules in the inner skin layer 12 and outer skin layer 13 is higher than that of the intermediate layer 11).

[0025] As a result, the hardness of the inner skin layer 12 and the outer skin layer 13 is higher than the hardness of the intermediate layer 11, and their thicknesses T2, T3 are thinner than the thickness T4 of the intermediate layer 11 (T2, T3 < T4).

[0026] In the cross-sectional structure of the grip 10, the boundaries between the skin layers 12, 13 and the intermediate layer 11 cannot be strictly distinguished, but in this embodiment, when observing the thermally-expandable microcapsules in the radial direction, the boundary between the two is defined as the portion where it can be evaluated that there are more elliptical thermally-expandable microcapsules 20' than spherical (circular) thermally-expandable microcapsules 20. Therefore, the portion where there are more elliptical thermally-expandable microcapsules 20' (outside the boundary) is the portion where the elliptical thermally-expandable microcapsules 20' increase and the hardness begins to increase.

[0027] The thickness, density, and hardness of each of the skin layers 12 and 13 can be adjusted appropriately by adjusting the amount of thermally expandable microcapsules directly filled into the mold, the heating temperature, the heating time, and other factors.

[0028] In this case, when the amount of thermally expandable microcapsules filled into the mold was changed and each molded product was observed, it was found that if the skin layers 12 and 13 were too thin, visible pinholes appeared, the hardness of the skin layers decreased, and problems with shape stability arose. Conversely, if the skin layers 12 and 13 were too thick, the intermediate layer 11 became too thin, losing elasticity and failing to obtain good elasticity (comfort in grip).

[0029] This is because, when the skin layers 12 and 13 are thin, the amount of thermally expandable microcapsules 20' decreases, resulting in a low specific gravity and brittle physical properties. On the other hand, when the skin layers 12 and 13 are thick, the amount of thermally expandable microcapsules 20' increases, but the specific gravity becomes high and the thermally expandable microcapsules are not foamed as much, which is thought to make them hard.

[0030] Based on these results, it is preferable to adjust the thicknesses T2 and T3 of the skin layers 12 and 13 to be thinner than the thickness T4 of the intermediate layer 11, and to adjust each of them to be in the range of 2 to 6% of the total thickness T. Specifically, if the thicknesses T2 and T3 of the skin layers 12 and 13 are secured to be about 100 μm, it is possible to achieve a coating structure that is moderately hard and provides elasticity when gripped.

[0031] More specifically, the density of the skin layers 12 and 13 is set to 0.22 to 1.2 g / cm 3 and for the intermediate layer 11, the density is set to 0.08 to 0.22 g / cm 3 It is preferable that the hardness of the skin layers 12 and 13 be set higher than the hardness of the intermediate layer 11.

[0032] Next, we will explain the results of a test comparing the grip (inventive product) with a conventional grip (a grip made of urethane foam with a specific gravity of 0.2; current product). This test (called a push-in test) typically measures the force with which an angler grips the grip, which is set to approximately 0.2 MPa. This was measured using a finger-shaped push-in jig to determine the load at which the pressure applied to the grip was 0.2 MPa. The set load was then applied repeatedly 10 times to both the inventive product and the current product, and the amount of sinking (deformation) was measured.

[0033] Figure 5(a) shows the test results for the inventive product for each number of repetitions, and Figure 5(b) shows the test results for the current product for each number of repetitions. As can be seen from these test results, the amount of displacement (mm) tends to gradually increase (shift to the right in the graph) as the number of repetitions increases, but as shown in the figures in the table in Figure 6, the average amount of plastic deformation for the inventive product was below 0.02 mm. In contrast, the average amount of plastic deformation for the current product exceeded 0.02 mm.

[0034] This means that the invented product has little plastic deformation even when gripped repeatedly, and maintains a certain degree of elasticity. In other words, it was confirmed that the invented product maintains sufficient elasticity compared to the current product, and that changes or deterioration in grip comfort can be prevented.

[0035] 7A and 7B are graphs comparing the maximum displacement (FIG. 7A) of the inventive product and the current product for each cycle of repeated testing (10 cycles each), and the amount of plastic deformation (FIG. 7B) of the inventive product and the current product. As can be seen from these comparison results, there is no significant difference in the maximum displacement between the inventive product and the current product even as the number of cycles increases. However, compared to the current product, the inventive product's maximum displacement is approximately 0.4 mm or less, indicating that there is no significant variation in grip comfort. In contrast, the current product's maximum displacement exceeds 0.5 mm, indicating that there is a constant large variation in grip comfort.

[0036] Regarding the amount of plastic deformation, although both products experienced a large amount of plastic deformation when first gripped (first time), the amount of plastic deformation was 0.126 mm for the invented product and 0.161 mm for the current product, resulting in a large amount of plastic deformation for the current product. As can be seen from this comparison result, the amount of plastic deformation for the invented product was small, and therefore the grip comfort did not change significantly even when gripped repeatedly.

[0037] The table in Figure 8 summarizes the evaluations (sensory evaluations) of fishing rods (carp rods) equipped with grips of the invention and the current product, when 10 testers actually used each fishing rod and caught fish.

[0038] Tester 2 shown in the table evaluated the current product as being "firmer to grip," and Testers 5 and 6 evaluated that there was not much difference in feel. However, seven Testers, namely Testers 1, 3, 4, and 7 to 10, evaluated that the invented product felt better than the current product, and the results showed that the invented product was more comfortable to grip than the current product.

[0039] The grip 10 described above is molded by filling a mold with fine particles of thermally expandable microcapsules, resulting in a lightweight, easy-to-process, and comfortable grip. Furthermore, simply filling a mold with fine particles of thermally expandable microcapsules and heating them allows the skin layers 12 and 13 to be integrally molded onto both sides of the elastic middle layer, simplifying the processing steps while improving the grip's strength. Furthermore, the inner skin layer 12 has high hardness, ensuring a stable fixation when bonded to the butt rod 1.

[0040] In addition, because the grip 10 is molded from the grip core material 10A, the freedom of the grip shape is increased, and the hard outer skin layer 13 makes it easier to form braiding and exterior patterns (coloring), etc., thereby improving grip, design, and strength.

[0041] Furthermore, since the grip is formed from a foamed thermal expansion capsule, it is possible to improve impact resistance, and it is also possible to exhibit shape retention and high strength.

[0042] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments and can be modified in various ways. In the above-described configuration, the grip 10 is formed separately from the rod and press-fitted and fixed with an adhesive. However, the base rod 1 may be positioned in a mold and the grip molded onto its outer periphery. Furthermore, with regard to a single material, in addition to the foamed thermal expansion capsule, it is also possible to appropriately modify the configuration by sequentially applying layers of the same resin material to form an inner skin layer, an intermediate layer, and an outer skin layer.

[0043] 1 butt rod 10 grip 10A grip core material 11 intermediate layer 12 inner skin layer 13 outer skin layer

Claims

1. A fishing rod grip that is attached to and gripped at the base end of a butt shaft of a fishing rod, said fishing rod grip comprising a grip core material molded from a single material, said grip core material having a three-layer structure comprising a middle layer and inner and outer skin layers that are harder than the middle layer and are provided on both sides of the middle layer.

2. The fishing rod grip according to claim 1, wherein the three-layer structure is formed by filling a mold with thermally expandable microcapsules.

3. A fishing rod grip as described in claim 2, characterized in that the thickness of each of the inner and outer skin layers is in the range of 2 to 6% of the overall thickness of the grip core material.

4. A fishing rod grip as described in claim 2, characterized in that, upon expansion of the thermally expandable microcapsules, the individual microcapsules of the inner and outer skin layers assume an elliptical shape and the individual microcapsules of the intermediate layer assume a circular shape, and the density of the inner and outer skin layers is higher than the density of the intermediate layer.

5. A fishing rod comprising a fishing rod grip according to any one of claims 1 to 4.

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