Fishing rod and method for forming joint structure

Abstract

The invention provides a fishing rod which can reduce loosening and buzzing on a joint part of a large-diameter rod and a small-diameter rod and is good in size precision. The fishing rod is provided with a joint structure (10) which enables the outer peripheral surface of the small-diameter part (5A) to be inserted into the inner peripheral surface of the large-diameter part (3A) and enables the small-diameter part (5A) and the large-diameter part (3A) to be jointed. A joining structure (10) is provided with: a straight joining section (10A); and an elastic member (20) that is press-fitted to an end portion of the small-diameter portion (5A) and that is provided with a joining portion (20B) that protrudes in the axial direction, the outer peripheral surface of the small-diameter portion (5A) and the outer peripheral surface of the joining portion (20B) being integrally centerless processed. The rod is characterized in that the diameter of the outer peripheral surface (20a) of the joint part (20B) is greater than the diameter D of the outer peripheral surface (5a) of the small-diameter rod by phi 0.03 mm to phi 0.06 mm relative to a centerless machining size (the diameter D of the outer peripheral surface (5a) of the small-diameter rod).

Description

Technical Field

[0001] Cross-reference This application claims priority based on Japanese patent application No. 2022-136272 (filed on August 29, 2022), the entire contents of which are incorporated herein by reference. The present invention relates to a fishing rod having a characteristic joint structure between adjacent large-diameter rods and small-diameter rods and a method for forming the joint structure. Background Art

[0002] Generally, a fishing rod having multiple rods is formed by connecting adjacent rods to each other through a connecting structure. As connecting structures, there are known plug-in type, reverse plug-in type, sleeve type, and pull-out type. By entering the connected state, the total length of the fishing rod can be extended, and by releasing the connected state, the contracted size of the fishing rod can be shortened.

[0003] As a joint structure, it is known that conical surfaces of different tapers are formed on the ends of adjacent large-diameter rods and small-diameter rods, respectively, and the respective conical surfaces are joined to each other. Since the fitting force of this joint structure is insufficient and it is easy to cause looseness and slackness, for example, as disclosed in Patent Document 1, there is known a joint structure in which an elastic component (rubber plug) is installed on the end of the small-diameter rod. This joint structure can join adjacent rods to each other and prevent looseness by making the elastic component protrude axially from the end of the small-diameter rod and forming a flange on the protruding portion, and then pressing the radial outer surface against the inner surface of the large-diameter rod.

[0004] Patent Literature Patent Document 1: Japanese Utility Model Application Laid-Open No. 63-109767 Summary of the invention

[0005] Although the joint structure disclosed in the above-mentioned patent document 1 is equipped with an elastic component on the end of the small-diameter rod, since the tolerance of the elastic component is at the level of 1 / 10mm, it is impossible to perform dimensional management with high precision when used in the joint structure. Generally, in a plug-in joint structure, when the gap between the outer circumference of the small-diameter rod and the inner circumference of the large-diameter rod is greater than 0.02mm, looseness and squeaking will occur. Therefore, it is difficult to perform dimensional management to prevent such looseness and squeaking under the tolerance of the above-mentioned elastic component. That is, due to the tolerance when the elastic component is formed, the size of the joint part cannot be controlled to a level that can be used as a product without causing problems. Therefore, post-processing is required when inspecting the product, so the manufacturing is labor-intensive and the cost is increased.

[0006] The present invention is made with a view to the above-mentioned problems, and the technical problem to be solved is to provide a fishing rod with a joint structure having good dimensional accuracy and capable of reducing looseness and squeaking at the joint between a large diameter rod (large diameter portion) and a small diameter rod (small diameter portion), as well as a method for forming such a joint structure.

[0007] In order to achieve the above-mentioned purpose, the fishing rod involved in the present invention has a joining structure in which the outer circumference of the small diameter part is inserted into the inner circumference of the large diameter part to join the two sides, and is characterized in that the joining structure has: a straight joint part; and an elastic component, which is pressed into the end of the small diameter part and has a joining part protruding in the axial and radial directions, and the outer circumference of the small diameter part and the outer circumference of the joining part are integrally processed by centerless machining, and the outer circumference of the joining part has a diameter larger than the centerless machining size by φ0.03mm~φ0.06mm.

[0008] In the fishing rod of the above structure, the outer peripheral surface of the small diameter part and the outer peripheral surface of the joint (flange) of the elastic member pressed into the small diameter part are integrally processed by centerless machining. When both are integrally processed by centerless machining, the joint part of the elastic member is subjected to a force extending in the axial direction by the pressing force during machining, while being cut into an outer peripheral surface identical to the outer peripheral surface of the small diameter part. Then, when the centerless machining is finished, the joint part in the state of extending in the axial direction is restored by elastic force and bulges in the radial direction. As for the radial bulge of the joint part, since it can be formed to be larger in diameter by φ0.03mm to φ0.06mm relative to the centerless machining size (the size of the outer peripheral surface of the small diameter part), it is possible to perform precise dimensional management at the level of 1 / 100mm, and when the small diameter part and the large diameter part are joined, the occurrence of looseness and chirping can be reduced. In addition, since precise dimensional management can be performed only by centerless machining, post-processing can be suppressed, thereby reducing the processing cost.

[0009] In addition, the present invention provides a method for forming a joint structure, wherein the joint structure is a joint structure in which the outer circumferential surface of a small diameter portion among a plurality of rods constituting a fishing rod is inserted into the inner circumferential surface of a large diameter portion of an adjacent rod to join the two portions, and the formation method is characterized in that the formation method comprises: an elastic component bonding step, in which an elastic component having a joint portion protruding axially and radially is pressed into and bonded to an end portion of the small diameter portion; and a surface treatment step, in which the small diameter portion and the joint portion protruding axially are centerlessly processed to a specified outer diameter size.

[0010] In such a forming method, since the outer diameter of the joint portion of the elastic component that is integrally processed with the small diameter portion can be precisely managed, the occurrence of looseness and squeaking can be reduced when the small diameter portion with the elastic component pressed in is engaged with the large diameter portion.

[0011] According to the present invention, it is possible to easily obtain a fishing rod and a joint structure that do not cause looseness or squeaking at the joint portion between a large-diameter rod (large-diameter portion) and a small-diameter rod (small-diameter portion) and have good dimensional accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a diagram showing the main part of one embodiment of the fishing rod according to the present invention. Figure 2 It is a pattern representation Figure 1 A diagram showing an end portion of a small diameter portion (small diameter rod shaft) of a fishing rod joint structure and an elastic member pressed into an opening of the end portion (before centerless machining). Figure 3 (a) to (c) are explained in order Figure 2 A diagram showing the processing steps of the joining portion. Figure 4 It is a diagram showing a second embodiment of the elastic member. Figure 5 It is a diagram showing a third embodiment of the elastic member. Figure 6 (a) means Figure 5 The figure shows the relationship between the elastic component and the small-diameter rod and the large-diameter rod, and (b) is a figure showing the state of the elastic component being bonded and fixed to the small-diameter rod. Figure 7 It is a diagram showing a fourth embodiment of the elastic member. Explanation of symbols 1-fishing rod; 3-first section of the rod (large diameter rod); 3A-large diameter part; 5-middle rod (small diameter rod); 5A-small diameter part; 10-jointing structure; 10A-straight joint part; 20-elastic component; 20B-joining part; 30-core material. DETAILED DESCRIPTION

[0013] Figure 1 It is a diagram showing the main part of one embodiment of the fishing rod according to the present invention. The fishing rod 1 involved in this embodiment is a structure in which a plurality of rods are connected in a plug-in manner, and each rod of the first rod section 3, the middle rod 5 and the tip rod 7 is connected to each other in the end area P thereof by a connection structure 10. At this time, there is no restriction on the number of middle rods (the total number of connected rods), and the tip rod 7 can also be a structure in which two rods are directly connected to the first rod section 3. Furthermore, the fishing rod may be provided with a fishing reel and a fishing line guide for guiding the fishing line.

[0014] The first rod section 3 and the middle rod section 5 are formed of a tubular body made of fiber-reinforced resin, and can be formed by, for example, winding a fiber-reinforced resin polyester film (prepreg film) in which reinforcing fibers (mainly carbon fibers or glass fibers, etc.) are impregnated with a synthetic resin such as epoxy resin onto a core shaft, and then de-coring the film after a heating process, etc., in accordance with conventional methods. In addition, similar to the first rod section 3 and the middle rod section 5, the tip rod section 7 can also be formed into a tubular body, and can also be formed of a solid body or a tubular body and a solid body.

[0015] Next, refer to Figure 2 and Figure 3 The joint structure 10 of the above-mentioned fishing rod 1 will be described. Figure 2 This is a diagram schematically showing the joint structure of the middle pole 5 side in the joint structure 10 of the adjacent first pole section 3 and the middle pole 5. Figure 3 (a) to (c) are explained in order Figure 2 At this moment, since the first rod section and the middle rod section are adjacent to each other and joined to form a tapered structure, in the following description, the first rod section 3 is referred to as a large-diameter rod section, and the middle rod section 5 is also referred to as a small-diameter rod section.

[0016] In this embodiment, a plug-in type is used as the joint structure 10. Therefore, the end of the small diameter rod 5 (also called the small diameter part 5A) is the male side, which is inserted and engaged with the end of the large diameter rod 3 (also called the large diameter part 3A), that is, the female side. That is, the large diameter part 3A is formed into a cylindrical shape, and the outer peripheral surface 5a of the small diameter part 5A is inserted into the inner peripheral surface 3a of the large diameter part 3A, so that the two sides are joined (in the structure Figure 3 In (b), the symbol L represents the axial connection length of the joint structure 10).

[0017] As described above, the adjacent and joined large-diameter rod 3 and small-diameter rod 5 are formed by winding prepreg film, and preferably, reinforcing prepreg film is wound at least on the portion of the joint length L. In addition, the prepreg film constituting each rod can use a prepreg film woven into a woven fabric with reinforcing fibers directed in the axial direction, the circumferential direction, or the oblique direction, and they can be used in appropriate combination.

[0018] The joint structure 10 has a straight joint portion 10A within the range of the joint length L in the axial direction. Figure 3 In (c), the axial connection length of the straight connection portion 10A is represented by the symbol L1. In this embodiment, a small diameter portion 5A and a large diameter portion 3A are connected to each other on both axial sides of a straight connection portion 10A. On the straight connection portion 10A, a gap G is generated between the outer peripheral surface 5a of the small diameter rod 5 and the inner peripheral surface 3a of the large diameter rod 3 during connection, and the following connection is performed on both axial sides thereof.

[0019] In this way, by providing a straight joint portion 10A on the joint structure, jointing is performed at two locations (point A and point B) on both sides of the axial direction. Compared with a structure in which a taper is formed in the area of ​​the straight joint portion for jointing, the joint portions become two locations separated in the axial direction. Compared with jointing at one location, an improvement in the joint force can be achieved. Of course, the joining structure may be constituted only by point A where the elastic member is provided.

[0020] The bonding structure at point A is constructed as follows. An elastic member (rubber plug) 20 is pressed and bonded to the end opening 5b of the small diameter portion 5A of the small diameter rod 5. The elastic member 20 is integrally formed by injecting silicone, nitrile rubber (NBR), etc. into a mold, and has a solid cylindrical portion 20A and a joint portion (flange) 20B formed on its end in a manner protruding in the radial direction. The joint portion 20B protrudes in the axial direction when the elastic member is bonded to the end opening 5b of the small diameter portion 5A. In addition, although the hardness varies depending on the material, if it is too soft, sufficient bonding force cannot be exerted at the joint. On the contrary, if it is too hard, resistance will be formed when it is joined with the large diameter rod, and there is a possibility that it will be difficult to slide. Therefore, it is preferably a hardness of about 60° to 80° under the Japanese Industrial Standard JIS standard (JIS K 6253).

[0021] The cylindrical portion 20A is formed to a size that can be pressed into the end opening 5b of the small diameter portion 5A, and is coated with an adhesive and pressed in and fixed (elastic member bonding step; Figure 3 (a)). The above-mentioned joint portion 20B is formed to a size that, when the cylindrical portion 20A is pressed into and bonded to the inner peripheral surface of the end opening 5b of the small diameter portion 5A, it protrudes in the axial direction and radially protrudes from the opening end edge 5B of the small diameter portion 5A. Specifically, the joint portion 20B is formed so that its outer diameter D1 becomes larger (about 0.5 mm) than the outer diameter D2 of the cylindrical portion 20A (see Figure 2 ).

[0022] As described above, in order to form a predetermined outer diameter, a known centerless machining machine is used to perform centerless machining (surface treatment process; see FIG. Figure 3(a)(b)). At this time, the outer peripheral surface 5a' of the small diameter portion 5A and the elastic member 20 bonded to the inner surface of the end opening 5b of the small diameter portion 5A are integrally processed by centerless machining. Therefore, the outer peripheral surface 20a' of the joint portion 20B of the elastic member 20 is also integrally cut. Since the centerless machining is performed until the outer peripheral surface 5a' of the small diameter portion 5A reaches a predetermined outer diameter D, the outer peripheral surface 20a' of the joining portion 20B is also processed until the outer peripheral surface 20a' reaches the same outer diameter D at the same time.

[0023] When the centerless machining is completed, the outer peripheral surface 20a of the joint 20B is slightly raised in the radial direction relative to the outer peripheral surface 5a of the small diameter portion 5A after the machining. That is, when the centerless machining is performed, the outer peripheral surface 20a of the joint 20B is slightly raised instead of the outer diameter D. The amount of this slight rise can be within the range of φ0.03mm to 0.06mm ((dD) = 0.03mm to 0.06mm) when the outer diameter of the raised outer peripheral surface 20a after the centerless machining is taken as d.

[0024] The bulge is formed by integrally performing centerless machining on the outer peripheral surface 5a' of the small diameter portion 5A and the outer peripheral surface 20a' of the joint portion 20B. Specifically, the joint portion 20B is formed by cutting the surface while being subjected to a force extending in the axial direction by the pressing force during machining, and when the centerless machining is completed, the joint portion 20B in the state of being stretched in the axial direction will be restored by its elastic force. That is, since the joint portion 20B is in a state restricted by the opening end edge 5B of the small diameter portion 5A, it will bulge in the radial direction by the contraction force at this time, thereby forming a bulge.

[0025] The bulge of the joint portion 20B depends on the hardness and size of the elastic member 20, but can be easily formed to be about φ0.03mm to φ0.06mm larger in diameter than the centerless processing size (the size of the outer peripheral surface of the small diameter portion 5A). That is, it can be easily bulged (formed into a bulge portion) with a tolerance of 1 / 100mm level. In addition, when the elastic member 20 is subjected to the centerless machining, the portion (the portion of the joint 20B) is raised in the radial direction, and the raised surface extends linearly in the axial direction. At this time, the surface raised in the radial direction may be variously expanded toward the rear end (becomes a tapered surface) according to the configuration of the elastic member 20, but in the present invention, the surface shape (surface state) of the raised portion is not particularly limited.

[0026] In addition, during the above-mentioned centerless machining, a machining process is performed in order to simultaneously form a bond at the point B. Specifically, such a joint portion can be formed by forming a tapered shape 5C in which the outer peripheral surface 5a' gradually expands in diameter as it moves away from the point A in the axial direction at the end portion on the opposite side of the straight joint portion 10A of the small-diameter rod 5.

[0027] On the straight joint portion 10A on the joint structure 10 between the small diameter rod 5 and the large diameter rod 3, the inner circumferential surface 3a of the large diameter rod 3 is formed to have the same diameter in the axial direction. Therefore, when the above-mentioned small diameter rod 5 is inserted into the large diameter rod 3, the taper 5C abuts against the open end edge 3A of the large diameter rod 3 to form a joint, and at the same time, the joint portion 20B of the elastic component 20 installed on the small diameter rod 5 is engaged with the inner circumferential surface 3a of the large diameter rod 3, thereby forming a joint on the two end sides (point A, point B) of the straight joint portion 10A (refer to Figure 3 (c)).

[0028] The above-mentioned joining structure 10 of the present embodiment will be described while enumerating specific dimensions. When the small diameter rod 5 with the outer diameter D of the outer peripheral surface 5a is joined to the large diameter rod 3 with the inner diameter D3 of the inner peripheral surface 3a, the inner diameter D3 is designed to be 10.00mm and the outer diameter D is designed to be 9.95mm. Thus, the gap G between the two rods when fitted is set to 0.05mm. At this time, since the inner peripheral surface 3a of the large diameter rod 3 is formed by a metal core shaft as described above, the tolerance does not increase, and the inner diameter D3 of the inner peripheral surface 3a of the large diameter rod 3 is formed in the range of about 10.0mm to 10.01mm.

[0029] Next, as mentioned above, Figure 3 The outer peripheral surface 5a' of the small diameter rod 5 shown in (a) and the outer peripheral surface 20a' of the joint 20B of the elastic component 20 bonded and fixed thereto are subjected to centerless machining. At this time, when the outer diameter D of the outer peripheral surface 5a of the small diameter rod 5 is taken as the design value and is subjected to centerless machining at 9.95mm, the outer peripheral surface 20a' of the joint 20B of the elastic component 20 shrinks after the above-mentioned centerless machining, and the diameter becomes larger by about φ0.03mm~φ0.06mm (bulge), so that the outer diameter d can be completed within the range of 9.98mm~10.01mm through this bulge.

[0030] Usually, in the joint structure of a large-diameter rod and a small-diameter rod, when the gap between the two is greater than 0.02mm, looseness or squeaking will occur. In the above-mentioned embodiment, by centerlessly machining the joint 20B of the elastic component 20 together with the outer peripheral surface of the small-diameter rod 5, the outer diameter d of the outer peripheral surface 20a of the joint 20B can be dimensionally managed at the level of 1 / 100mm. That is, relative to the inner diameter D3 of the inner peripheral surface 3a of the large-diameter rod 3 of about 10.0mm to 10.01mm, the outer diameter d of the outer peripheral surface 20a of the joint 20B can be completed to 9.98mm to 10.01mm. In this way, since the gap size between the outer circumference of the joint 20B and the inner circumference of the large diameter rod can be managed to be less than 0.02 mm, there is no need to consider tolerance even if the elastic component 20 is used, thereby preventing looseness or squeaking at the joint when the two rods are fitted together.

[0031] In addition, according to the above-mentioned method of forming the joining structure, since the size of the joining portion 20B can be managed precisely at the 1 / 100mm level, the post-processing operation process can be suppressed when inspecting product operations, and the post-processing is used to reduce the occurrence of looseness or squeaking, thereby reducing processing costs.

[0032] Furthermore, in the above-described configuration, since the elastic member 20 is installed in the end opening 5b, an impact mitigation effect when the rod falls can be obtained, and an effect of preventing a rod with a small diameter from falling out can be obtained when it is stored inside.

[0033] Next, other embodiments of the present invention will be described. In the following embodiment, the same reference numerals are used to denote the same components as those in the above embodiment, and detailed description thereof will be omitted.

[0034] Figure 4 It is a diagram showing a second embodiment of the elastic member. In this embodiment, the elastic member 20 is not formed solid but hollow (cylindrical portion 20A'). Thus, by forming the portion of the elastic member 20 bonded to the small-diameter rod into a hollow shape, the weight of the joint structure can be reduced.

[0035] Figures 5 to 7 It is a diagram showing a third embodiment of the elastic member. In this embodiment, similar to the second embodiment, the elastic member is formed into a hollow shape (cylindrical portion 20A'), and a groove 21 is formed in an annular or spiral shape on the outer peripheral surface of the cylindrical portion 20A'. Since the groove 21 has the function of serving as an adhesive storage portion, the adhesive force between the small-diameter rod 5 and the elastic member 20 can be improved.

[0036] Furthermore, it is preferable that the axial length of the elastic member 20 , that is, the length L3 of the cylindrical portion 20A′ and the length L4 of the joining portion 20B are set as follows. First, if the axial length L3 of the cylindrical portion 20A' is too short, sufficient bonding strength cannot be obtained, and if it is too long, flexibility will be affected or weight will increase, so it is preferably formed in the range of 10.0 mm to 25.0 mm. In addition, if the axial length L4 of the joint portion 20B is too short, sufficient fitting strength cannot be obtained, and if it is too long, sliding properties during jointing will be affected, so it is preferably formed in the range of 3.0 mm to 5.0 mm.

[0037] The above-mentioned axial lengths L3 and L4 can be formed based on the outer diameter D2 of the cylindrical portion 20A' (the outer diameter of the portion without the groove) and the outer diameter D1 of the joint 20B before processing. Specifically, if the outer diameter D2 of the cylindrical portion 20A' is less than 10.0 mm, L3 can be about 20.0 mm, and if the outer diameter D2 is greater than 10.0 mm, L3 can be about 25.0 mm. In addition, if the outer diameter D1 of the joint 20B is less than 12.0 mm, L4 can be about 4.0 mm, and if the outer diameter D1 is greater than 12.0 mm, L4 can be about 5.0 mm.

[0038] like Figure 6 As shown in (a), when the elastic component 20 is pressed into the small diameter rod 5 and fixed by bonding, the inner diameter D4 of the inner circumference 5c of the small diameter rod 5 is formed by a metal core shaft as described above, so the tolerance does not become large and can be formed within a range of about +0.01mm relative to the design value. In addition, for the elastic component 20, since the groove 21 that serves as the adhesive storage portion is formed as described above, and the adhesive (Cyanon 721, etc.) is applied thereto, and it is pressed and bonded to the inner circumference of the small diameter rod 5, the outer diameter D2 of the cylindrical portion 20A' is preferably smaller than the inner diameter D4 of the small diameter rod 5 as a design value (a smaller diameter of about -0.05mm to -0.1mm relative to the inner diameter D4). That is, although the tolerance of the elastic component 20 is relatively large (1 / 10mm level) as mentioned above, if a design value of a somewhat smaller diameter is adopted in advance for the inner diameter D4, the presence of the groove 21 as an adhesive storage portion can ensure sufficient bonding strength even when the actual outer diameter is smaller. Furthermore, conversely, even when the actual outer diameter is larger, the resistance during pressing can be reduced, thereby enabling the elastic component 20 to be pressed into and bonded to the small diameter rod 5.

[0039] Then, after the elastic member 20 is pressed and bonded to the inner circumference 5c of the small diameter rod 5, the centerless processing as described above is performed. By this centerless processing, the outer diameter d of the joint 20B is larger than the outer diameter D of the outer circumference of the processed small diameter rod 5 by about φ0.03mm to φ0.06mm (see Figure 6 (b)).

[0040] In this way, the small-diameter rod 5 to which the elastic member 20 is bonded and fixed and the centerless processing is performed is joined to the large-diameter rod 3 (see Figure 6 (a)). At this time, although the inner diameter D3 of the inner circumference 3a of the large-diameter rod 3 has a tolerance of about 0 to 0.01 mm relative to the design value, the outer diameter d of the outer circumference 20a of the joint 20B can be formed, through centerless machining, between the outer circumference D of the small-diameter rod so that a gap of less than (about 0.02 mm) can be formed without causing squealing when joined.

[0041] In addition, if Figure 7 As shown, it is preferred that a core material 30 is pressed and fixed in the inner hollow portion 22 of the cylindrical portion 20A' of the elastic member 20 constructed as described above. The core material 30 may be made of metal, resin, cork, etc., and by pressing and bonding after centerless processing, the outer diameter of the joint 20B can be increased. That is, when the joint force is weak, the joint force can be adjusted by pressing and bonding such a core material 30. In addition, by pressing and bonding the core material 30, it is not easy to cause large deformation when releasing the joint, and no deformation will occur during the joint. Figure 7 There is no inconvenience such as cracks occurring on the P1 portion (the joining portion between the joining portion 20B and the opening end edge 5B of the small-diameter rod 5) or twisting of the fitting portion.

[0042] Although the embodiments of the present invention have been described above, the present invention is characterized in that, when forming the joint structure, the outer peripheral surface of the rod and the elastic component pressed into the end opening of the rod are integrally processed without centering, and the other structures are not limited to the above-mentioned embodiments, and various changes can be made.

[0043] The specific structure of the joint structure of the present invention is not specified, as long as there is a straight joint between the small diameter part and the large diameter part. Therefore, the joining of the two rods can also be performed only on the part of the above-mentioned elastic component. In addition, for the joint part (flange) of the elastic component 20, although its size is formed by a mold, in order to facilitate centerless processing, it is preferably formed to be about 0.5 to 1.0 mm larger than the outer diameter D2 of the cylindrical part 20A.

[0044] Furthermore, in addition to the above-mentioned plug-in type, the fishing rod joint structure 10 according to the present invention can also be applied to an inverted plug-in type or a sleeve type. That is, in the reverse plug-in type joint structure, the end of the small-diameter rod 5 is the large-diameter portion (female side), and the end of the large-diameter rod 3 is the small-diameter portion (male side). In addition, in the sleeve type joint structure, in the case where the sleeve (core material) is pressed and fixed on the end of the large-diameter rod 3, the end of the small-diameter rod 5 is the large-diameter portion (female side), and the exposed sleeve is the small-diameter portion (male side); in the case where the sleeve (core material) is pressed and fixed on the end of the small-diameter rod 3, the end of the large-diameter rod 3 is the large-diameter portion (female side), and the exposed sleeve is the small-diameter portion (male side).

[0045] The above-mentioned specific dimensions are only examples, and can be appropriately modified according to the type of fishing rod, the thickness of the small diameter part and the large diameter part, etc. At this time, although the outer diameter d of the outer peripheral surface of the joint 20B of the elastic member 20, 20' after the centerless processing is larger than the diameter of the outer peripheral surface of the small diameter part (small diameter rod) (in the embodiment, the diameter is larger by φ0.03mm to φ0.06mm), it is sufficient to select the material so that the bulge amount is within this range. In addition, the bulge amount is not limited to φ0.03mm to φ0.06mm, and can be appropriately changed according to the thickness or type of the fishing rod (as long as it is formed to be larger than φ0mm).

Claims

1. A fishing rod having a joint structure in which the outer peripheral surface of a small diameter portion is inserted into the inner peripheral surface of a large diameter portion to join the two, characterized in that: The joint structure comprises: a straight joint portion; and an elastic member, which is pressed into the end of the small diameter portion and has a joint portion protruding in the axial direction and the radial direction, The outer peripheral surface of the small diameter portion and the outer peripheral surface of the joining portion are integrally processed by centerless machining, and the outer peripheral surface of the joining portion has a diameter larger than the centerless machining size by φ0.03 mm to φ0.06 mm.

2. The fishing rod according to claim 1, characterized in that: The elastic component is a cylindrical solid structure or a hollow structure.

3. The fishing rod according to claim 1, characterized in that: The elastic component is a hollow structure, and a core material is bonded and fixed in the inner cavity of the elastic component.

4. The fishing rod according to claim 1, characterized in that: The elastic member press-fitted into the end portion of the small diameter portion has an adhesive reservoir formed therein for applying the adhesive between the elastic member and the inner peripheral surface of the small diameter portion.

5. The fishing rod according to claim 1, characterized in that: The joint structure forms a joint between the small diameter portion and the large diameter portion on both axial sides of the straight joint portion.

6. A method for forming a joint structure, wherein the outer peripheral surface of a small diameter portion of a plurality of rods constituting a fishing rod is inserted into the inner peripheral surface of a large diameter portion of an adjacent rod to join the two, characterized in that: have: an elastic member bonding step of pressing and bonding an elastic member having a joint portion protruding in the axial direction and the radial direction to an end portion of the small diameter portion; and a surface treatment step, wherein the small diameter portion and the engaging portion protruding in the axial direction are centerlessly processed to a predetermined outer diameter dimension.

7. The method for forming a bonding structure according to claim 6, wherein: After the centerless machining is performed, the outer diameter of the joint portion is machined to be larger by φ0.03 mm to φ0.06 mm than the centerless machining size.

8. The method for forming a bonding structure according to claim 6, wherein: The elastic member has a hollow structure, and after the centerless processing is performed, a core material is bonded and fixed in the inner hollow portion thereof.

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