JPH0229500B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a composite tubular body formed by connecting two or more types of prepreg sheets made of fibers with different elastic modulus and bending strength, and particularly to a composite tubular body suitable for forming a fishing rod. Regarding a tubular body. (Prior Art) In recent years, fishing rods made of carbon fiber, glass fiber, aramid fiber, alumina fiber, etc. have been commonly used. These fishing rods are made by making prepreg sheets by aligning these carbon fibers or making them into woven or non-woven fabrics and impregnating them with thermosetting resin, such as epoxy resin, in an uncured state. A prepreg sheet is wound around an axis along the longitudinal direction of the fibers to form a tubular body, which is then heated and hardened. And, like natural bamboo, the diameter gradually increases from the thin tip to the root, and it has been considered optimal to have natural flexure as a whole. However, fishing rods made of single fibers such as carbon fiber, glass fiber, aramid fiber, or alumina fiber are made of the same material from the tip to the base. With a coefficient of 24t/mm ² ), there is a problem that the rigidity of the entire rod is increased and natural flexure cannot be obtained at the tip, resulting in a decrease in the so-called strike sensitivity. Also, for materials with low bending rigidity such as glass fiber (modulus of elasticity: 0.7t/mm ² ), aramid fiber (modulus of elasticity: 1.2t/mm ² ), and alumina fiber (modulus of elasticity: 1.2t/mm ² ). Although the tip is given a natural bend and the so-called hit sensitivity is suitable, the rigidity of the entire rod is reduced and the entire rod is bent significantly, making it difficult to handle. Also, as shown in Figure 11, the rod a on the tip side of the fishing rod
For example, a tubular member made of a prepreg sheet of glass fiber is used for the rod, a tubular member made of a prepreg sheet of carbon fiber is used for the rod b on the base side, and a tubular member made of a prepreg sheet of carbon fiber is used for the rod rod b on the base side. A connecting rod in which a cylindrical or rod-shaped connecting member d extending over each of a and b is inserted and connected is known. When using such a configuration, the tip side rod a and the base side rod b
Since the bending strength of the connecting part c between the two ends is extremely different, a phenomenon occurs in which the rod a on the tip side bends, but the rod rod b on the base side does not bend, resulting in excessive force being applied to the connecting part c, and sometimes the connecting part c could be damaged, and it was impossible to require the entire fishing rod to have natural bending. (Problems to be Solved by the Invention) The present invention eliminates such conventional inconveniences and provides a composite tubular body that has natural flexure as a whole like natural bamboo without causing damage to the joints. This is what I am trying to do. (Means for Solving the Problems) The present invention has been made to solve the above problems, and provides a first prepreg sheet made of aligned carbon fibers and impregnated with a thermosetting resin, and a glass fiber. , a second prepreg sheet made of an aligned or woven fabric of one or more fibers selected from aramid fibers or alumina fibers impregnated with a thermosetting resin, in which an uncured thermosetting resin is used. The side edge of the first prepreg sheet impregnated with carbon fibers that intersects with the direction of alignment of the carbon fibers is 25 to
The side edges of a second prepreg sheet formed at an angle of 70 degrees and impregnated with an uncured thermosetting resin are connected to form a composite part, and the fibers of the first prepreg sheet are connected. Both sheets are wound around a mandrel along the alignment direction to form a tubular body, the joined portion is formed in a spiral shape that goes around the circumference of the tubular body at least twice, and the thermosetting resin is heated. It is characterized by being hardened. (Function) Since the present invention employs the above configuration, the ratio of the first prepreg sheet having a higher bending strength among both prepreg sheets at the joint portion of the tubular body is the first prepreg sheet.
2nd layer with lower bending strength from the prepreg sheet side
The bending strength gradually decreases from the first prepreg sheet side where the rigidity is high to the second prepreg sheet side where the rigidity is low. Significant differences in bending strength between sections are eliminated. If the inclination angle Θ of the side edge forming the joint of the first prepreg sheet is 25 degrees or more, the linear expansion coefficient (coefficient value = 0) of the carbon fiber of the first prepreg sheet and the glass of the second prepreg sheet Fiber (coefficient value = 3.2×10 ^-6 /℃), aramid fiber (coefficient value = -2.0×10 ^-6 /℃), alumina fiber (coefficient value =
Despite the extremely large difference in linear expansion coefficient (8.8×10 ^-6 /°C), both prepreg sheets polymerize moderately at the joint, and the proportion of each fiber becomes appropriate. Therefore, when this is formed into a tubular body and the impregnated thermosetting resin is heated and cured, there is no possibility that the bonded portion will be distorted and bent due to the difference in linear expansion. Furthermore, even when the inclination angle Θ is close to 70 degrees, the rigidity and bending strength of the joint region when both prepreg sheets are moderately polymerized at the joint and formed into a tubular body are second to none. The bending strength is greater than that formed only from the fibers of the prepreg sheet, and the difference in bending strength from the tubular body portion formed only from the first prepreg sheet is reduced. Furthermore, when both sheets are formed into a tubular body, the joint portion is formed in a spiral shape, and the spiral joint portion turns around the tubular body two or more times. 2. The area where the material overlaps with the prepreg sheet is expanded to strengthen the bending strength of the bonding area itself. (Example) A more detailed explanation will be given with reference to FIGS. 1 to 5 showing an example of implementation of the present invention. In the drawings, 1 is a first prepreg sheet formed by aligning a large number of carbon fibers 1a and impregnating them with an uncured thermosetting resin 1b made of epoxy resin as shown in the first figure, and 2 is a large number of glass fibers. This is a second prepreg sheet formed by impregnating a thermosetting resin 2b made of epoxy resin into a woven fabric woven with 2a. In the second prepreg sheet 2, aramid fibers or alumina fibers can be used instead of glass fibers, and these fibers can be used alone or in combination. The side edges 3 of the first prepreg sheet 1 that intersect with the direction in which the carbon fibers are aligned are set at an angle Θ of 25 degrees to 70 degrees with respect to the direction in which the fibers are aligned through the center of the sheet 1, as shown in the first figure. Formed. Then, the side edges 4 of the second prepreg sheet 2 are butted against the side edges 3 of the first prepreg sheet 1, and the side edges 3 and 4 are heated to melt the impregnated epoxy resins 1b and 2b. , a tape 5 made of a glass scrim sheet is attached to the joint 6.
was formed. Instead of the glass scrim sheet, a carbon fiber nonwoven fabric can be used, and a paper sheet can also be used. Both sheets 1 and 2 joined in this way are
It was wound around a mandrel 7 shown by phantom lines in the figure to form a tubular body 8 shown in the second figure. When forming this tubular body 8, both sheets 1,
2 was wound around the mandrel 7 two or more times so that the joint 6 was formed in a spiral shape around the tubular body 8 two or more times. Next, a tape was wound around the mandrel 7 and heat treatment was performed to harden the impregnated thermosetting resin, and after cooling, the mandrel 7 was pulled out and completed. Since the tubular body 8 manufactured in this way has the joint portion 6 arranged in a spiral shape as shown in the third figure, the ratio of the first prepreg sheet 1 to the second prepreg sheet 2 in this region is The closer to the first prepreg sheet 1 side, the higher the ratio of carbon fiber becomes, and the closer to the second prepreg sheet 2 side, the lower the ratio becomes, and conversely, the ratio of glass fiber increases. Therefore, in this joint region, the bending strength gradually decreases from the first prepreg sheet 1 side, which has high rigidity, to the second prepreg sheet 2 side, which has low rigidity, and gradually decreases over the entire length of the tubular body 8. Gives the property that the ease of bending changes. In the embodiment, the side edges 3, 4 of both sheets 1, 2
Tape 5 made of glass scrim sheet
However, when the tape 5 is a heat-melting synthetic resin film that easily adheres to both sheets 1 and 2, such as a hot melt type epoxy resin film or polyester resin film, when joining Second, by heat-pressing the tape 5, it is possible to melt the tape 5 and eliminate the thickness of the tape 5. Further, as a structure for joining both sheets 1 and 2, the configurations shown in FIGS. 4 to 10 can be adopted. FIG. 4 shows that the side edges 3 and 4 of both sheets 1 and 2 are butted together, and the abutted portions of both side edges 3 and 4 are heated.
Uncured thermosetting resin 1 impregnated in the part
b, 2b are melted and both side edges 3, 4 are adhered. At this time, the side edges 3 and 4 of both sheets 1 and 2 may be overlapped with each other, but this is not preferable since a step will be formed in the joint portion 6 when the thickness of each sheet 1 and 2 is large. The embodiments shown in FIGS. 5 to 8 are for both sheets 1 and 2.
1 and 2 respectively show the bonding structure when two or more layers are used. In the embodiment shown in FIGS. 5 and 6, the first prepreg sheet 1 is composed of an upper layer 10 and a lower layer 11, and the upper layer 10 and the lower layer 11
They were made to protrude further outward and were bonded together. In addition, the second prepreg sheet 2 is formed into an upper layer 10 and a lower layer 2.
1 and a lower layer 21 at the side edge forming the joint.
were formed by protruding outward from the upper layer and adhering to each other. Then, as shown in Figure 5, the sheets 1 and 2 were abutted and welded together under heat and pressure, and bonded using the thermosetting resins 1b and 2b impregnated into both sheets 1 and 2. In the embodiments shown in FIGS. 7 and 8, both sheets 1 and 2 are
It is constructed by laminating three layers, respectively. In FIG. 7, the upper layer 110, middle layer 111, and lower layer 112 of the first prepreg sheet 1 are stacked in a stepwise manner while being shifted from each other at the side edges forming the joint portion, and are then laminated and bonded to each other. The upper layer 210, the middle layer 211, and the lower layer 212 of the plague sheet 2 are stacked in a stepwise manner with the side edges forming the joint section shifted in the same manner, and both sheets 1 and 2 are butted together and heat pressure welded in the same manner as in the previous embodiment. Then, they were bonded and bonded using thermosetting resins 1b and 2b. FIG. 8 shows a modification of the embodiment shown in FIG. 7, in which an intermediate layer 211 is formed to protrude from the upper layer 210 and the lower layer 212 at the side edge forming the joint part of the second prepreg sheet 2, while the first The prepreg sheet 1 conversely has an upper layer 110 and a lower layer 112 as an intermediate layer 11.
1, and both sheets 1 and 2 were abutted against each other and bonded by heat and pressure in the same manner as in the previous embodiment and bonded with thermosetting resins 1b and 2b. 9 and 10 show a modification of the embodiment shown in FIGS. 5 and 6, in which an upper layer 10 and a lower layer 11 are connected at the side edge forming the joint of the first prepreg sheet 1.
Similarly, the upper layer 20 and the lower layer 21 of the second prepreg sheet 2 are stacked with their inclination directions reversed, and both sheets 1 and 2 are butted against each other as shown in FIG. They were bonded by heat-pressure welding and bonded using thermosetting resins 1b and 2b in the same manner as in the example. In the above embodiments, the second prepreg sheet 2 is made of woven fabric, but the object of the present invention can also be achieved using a prepreg sheet made of aligned glass fibers. Next, more specific examples will be described. The basic configuration adopted is the configuration shown in FIGS. 1 to 3. A carbon prepreg sheet 1 with a thickness of 0.16 mm, a basis weight of 150 g/m ² , a sheet size of 50 mm in width, and a length of 300 mm is formed by aligning carbon fibers and impregnating them with epoxy resin, and glass fiber with product number #182 is woven into the sheet. Formed by impregnating woven fabric with epoxy resin, thickness 0.18 mm, basis weight 220 g/m ² , sheet dimensions width 50
A glass prepreg sheet 2 with a length of 300 mm and a length of 300 mm was used. The inclination angle Θ of the side edge 3 forming the joint part 6 of the carbon prepreg sheet 1 (width W of the joint part that changes correspondingly) was manufactured in various ways as shown in Table 1, The side edge 4 of the glass prepreg sheet 2 was butted against the side edge 3 of the sheet 1, and a tape 5 made of a glass scrim sheet was bonded across both sheets 1 and 2 to join them. Next, both sheets 1 and 2 are wound around a mandrel to form a tubular body, and the joined portion is formed into a spiral structure with four turns around the tubular body, and heat-cured (temperature: 130°C,
The material was manufactured by heat curing using a heating time of 1.5 hours. Table 1 shows the bending strength of the joint region of each tubular body manufactured in this manner and the presence or absence of bending due to heating deformation of the joint after molding.

【table】

[Table] The method for measuring bending strength is to set a fixed point P at a position 10 mm from the midpoint S of the joint area toward the area formed by the carbon prepreg sheet, and from this fixed point to the area formed by the glass prepreg sheet. Load point X is a position 300 mm away from the area where the
Measurements were made by applying a load at a speed of mm. (See FIG. 2) The presence or absence of bending deformation was determined by visually observing the bending state with respect to the axis at load point X after applying the maximum load of the bending strength test. As a result, in Comparative Example 1 where the inclination angle Θ was 78 degrees, the bending strength was only approximately the same as the bending strength of the tubular body formed only from the glass prepreg sheet 2 (60 kg/mm2 ⁾ , and the bending strength in the joint region Damage occurred in the part formed from the glass prepreg sheet. In addition, in Comparative Example 2 where the inclination angle Θ is 11 degrees, the bending curvature of the tubular body formed only from the carbon prepreg sheet 1 is 115 kg/mm ² and the bending strength of the tubular body formed only from the glass prepreg sheet. Although the strength was improved, the restorability was poor and bending deformation remained. Next, when the carbon prepreg sheet 1 and the glass prepreg sheet 2, which were created in the same manner as above, are bonded together and formed into a tubular body, the number of times the bonded portion turns around the tubular body is determined. Tested for changes. The results are shown in Table 2.

【table】

[Table] The measurement method was the same as the test in Table 1 above. As is clear from the above results, when the tubular body is formed, it is necessary that the joint portion turns around the tubular body two or more times, preferably three or more times. (Effects of the Invention) As is clear from the above, the present invention has an advantage that the ratio of carbon prepreg sheets in both prepreg sheets in the joint region of the tubular body is changed from the carbon prepreg sheet side to the glass prepreg sheet side. Along with this, the bending strength also gradually decreases from the carbon prepreg sheet side, which has higher rigidity, to the glass prepreg sheet side, which has lower rigidity, resulting in a noticeable difference in bending strength and rigidity. Since this is eliminated, it is possible to provide a composite tubular body that has natural flexure like natural bamboo throughout without damaging the joint area.

[Brief explanation of drawings]

1 to 3 show an example of the implementation of the present invention, FIG. 1 is a partially cutaway developed view before forming a tubular body, FIG. 2 is a side view of the formed tubular body, and FIG. 3 is a side view of the formed tubular body.
The figures are a cross-sectional view taken along the line -- in Figure 2, and Figures 4 to 1.
0 shows a bonding structure between a carbon prepreg sheet and a glass prepreg sheet, FIG. 4 is a partially broken developed view showing a bonded part of another embodiment of the present invention, and FIGS. 5 and 6 are FIG. 5 is an explanatory diagram showing a state before joining, showing another joining structure of the present invention;
6 is a sectional view of the bonded state in FIG. 5, FIGS. 7 and 8 are sectional views of the bonded portion of another embodiment of the present invention, and FIG. 9 and 10 are 9 is an explanatory diagram showing the state before joining, and FIG. 10 is a cross-sectional view of the joined state in FIG. 9.
FIG. 11 is a partially cutaway side view of the conventional example. DESCRIPTION OF SYMBOLS 1... First prepreg sheet, 1a... Carbon fiber, 1b... Thermosetting resin, 2... Second prepreg sheet, 2a... Glass fiber, 2b...
...Thermosetting resin, 3, 4...Side edge, 6...Joint part.

Claims (1)

[Claims] 1. A first prepreg sheet made of aligned carbon fibers and impregnated with a thermosetting resin, and glass fibers;
1 selected from aramid fiber or alumina fiber
In a composite tubular body consisting of a second prepreg sheet made of aligned or woven fibers impregnated with a thermosetting resin, carbon of the first prepreg sheet impregnated with an uncured thermosetting resin; The side edges that intersect with the alignment direction of the sheet are formed at an angle of 25 to 70 degrees with respect to the alignment direction of the fibers passing through the center of the sheet, and the side edges are impregnated with an uncured thermosetting resin. The side edges of the second prepreg sheet are connected to form a joint, and both sheets are wound around a mandrel along the direction in which the fibers of the first prepreg sheet are aligned to form a tubular body. A composite tubular body, characterized in that the thermosetting resin is formed into a spiral shape that goes around the circumference of the tubular body at least twice, and the thermosetting resin is heated and cured. 2 The joint portion abuts the side edge of the first prepreg sheet and the side edge of the second prepreg sheet, and the uncured thermosetting resin of the butted sheets is heated to bond both side edges. A composite tubular body according to claim 1, characterized in that: 3. The joint portion is characterized in that the side edge of the first prepreg sheet and the side edge of the second prepreg sheet are butted against each other, and the connection is made by pasting tape on at least one surface of both side edges. Composite tubular body according to scope 1. 4. The composite tubular body according to claim 3, wherein the tape is made of a heat-fusible film. 5. The joining portion abuts the side edge of the first prepreg sheet and the side edge of the second prepreg sheet, and a glass scrim sheet integrally adhered to either one of both sheets is superimposed on both side edges,
2. The composite tubular body according to claim 1, wherein the glass scrim sheet is polymerized and the uncured thermosetting resin of both sheets is heated to bond both side edges. 6. The joining portion abuts the side edge of the first prepreg sheet and the side edge of the second prepreg sheet, and polymerizes the carbon nonwoven fabric integrally adhered to either one of both sheets on both side edges, and 2. The composite tubular body according to claim 1, wherein the uncured thermosetting resin of both sheets in which the carbon nonwoven fabric is polymerized is heated to bond both side edges together. 7. The first prepreg sheet and the second prepreg sheet are composed of a laminate of at least two or more layers, and the bonding portion is abutted against each other with the stacked positions shifted at the side edges of each sheet, so that the layers overlap each other,
2. The composite tubular body according to claim 1, wherein the uncured thermosetting resins of both of the polymerized sheets are bonded together by heating.