JPH09290463A - Tubular member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the gradual reduction in the wall thickness of the end part region of a reinforcing layer by almost turning the reinforcing fibers of the reinforcing layer in the circumferential direction of a tubular member, to prevent the sudden change of a cross section state, to make the reinforcing fibers of a main body hard to twist and to prevent the molding bending of the tubular member. SOLUTION: This tubular member containing a synthetic resin as a matrix and reinforced by reinforcing fibers contains reinforcing fibers 12S arranged in the vicinity of the end part of the main body layer 10J continued from the inward part in the axial direction of the tubular member to the end part thereof and almost turned in the circumferential direction of the end part as a main component and has a reinforcing layer 12H wherein the end part region 12K on the side of the inward part is gradually reduced in thickness toward the inward part over the axial direction length L equal to or more than the wall thickness dimension (t) in the vicinity of the other end part of the layer 12H.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tubular body which has a thermosetting or thermoplastic resin as a matrix and is reinforced with reinforcing fibers. Therefore, it relates to fishing rods, golf club shafts, ski poles, bicycle frames, tennis and badminton rackets, and the like.

[0002]

2. Description of the Related Art In order to form a tubular body with a so-called prepreg (including not only a thermosetting resin but also a thermoplastic resin), a prepreg is wound around a core metal and then heat-formed while applying pressure. To do. At the time of this forming, in a state in which the cut prepreg is wound around the core metal, an overlapping portion between the winding start edge portion and the end edge portion of the prepreg is generated, and this overlapping portion is the meat in the circumferential direction of the tubular body. If it becomes a peculiar portion of thickness and physical properties, and this peculiar portion exists at the same circumferential angular position along the axial direction of the tubular body, the bending of the tubular body occurs due to the temperature change due to the heat molding. Further, when thickening the end portion of the tubular body, if only reinforcement is taken into consideration, the thickness will suddenly become thicker near the end portion. However, this tends to cause turbulence and other disturbances in the reinforcing fibers of the main body layer near the end portion reinforced during heat molding, which reduces the strength of the molded tubular body and tends to cause molding bending. Further, in the structure in which the diameter of the tubular body changes abruptly in the axial direction, the prepreg is likely to be wrinkled in the vicinity of such a sudden change boundary, and the reinforcing fibers are disturbed. Such disorder of the reinforcing fibers causes bending of the tubular body formed by heating. Further, the winding of the tightening tape for pressurizing the wound prepreg causes wavy bending of the axial reinforcing fibers. Such bending is corrected in a correction process after molding, but if it is still not corrected, it becomes a defective product.

[0003]

However, such a correction process takes time and the manufacturing efficiency is lowered, and at the same time,
In some cases, the product may not be completely repaired, and some deformation may remain in the end, which easily deteriorates the product quality. In addition, if defective products are produced, the yield becomes worse, which causes a cost increase.

Accordingly, the present invention aims to provide a tubular body of low quality and high quality.

[0005]

In view of the above object, the present invention is a tubular body reinforced with reinforcing fibers, which is made of synthetic resin as a matrix, and extends from the inner side to the end in the axial direction of the tubular body. Is disposed near the end of the continuous main body layer and has mainly reinforcing fibers oriented in a substantially circumferential direction, and the end region on the inner side is equal to or larger than the wall thickness dimension near the other end. The tubular body is provided with a reinforcing layer whose wall thickness is gradually reduced in the direction of the inner portion over the axial length.

When the prepreg of the reinforcing layer and the prepreg of the main body layer are overlapped with each other, the reinforcing fiber of the main body layer is generally easily twisted at the time of pressure molding in the vicinity of the boundary between the main body layer prepreg and the end of the reinforced prepreg. When the reinforcing fibers of the reinforcing layer are oriented substantially in the circumferential direction of the tubular body, it is easy to gradually reduce the wall thickness of the end region of the reinforcing layer, and thus the end region of which the wall thickness is gradually reduced is In the vicinity of the boundary where the prepreg of the reinforcing layer and the prepreg of the main body layer, which are located on the one side, overlap, the degree of change in the cross-sectional state is mitigated, so that the axial reinforcing fibers are difficult to twist, and tubular bending is prevented. To be done.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail with reference to an embodiment shown in the accompanying drawings. FIG. 1 shows an example of a fishing rod tube as a tubular body according to the present invention, and shows a rod tube 10 made of fiber reinforced plastic using reinforcing fibers such as carbon fibers. The front end portion 10E (or the rear end portion) of the rod tube 10 is generally reinforced as compared with other regions in order to secure the joining strength. An enlarged cross-sectional view of the B portion of the front end portion 10E is shown in FIG. Corresponding to the main body layer 10J in order to reinforce the end portion of the main body layer 10J which mainly has reinforcing fibers oriented in the axial length direction and which is continuous from the inner portion to the end portion in the axial length direction of the rod tube 10. When a prepreg 12H ′ (schematically shown in FIG. 3) corresponding to the reinforcing layer 12H mainly having the reinforcing fibers 12S oriented substantially in the circumferential direction is superposed on the end of the prepreg to be wound around the core metal, 2, the main body layer 10J
The end portion 10E in which the reinforcing layer 12H is disposed is formed between the layers.

In the present invention, the prepreg 12 corresponding to the reinforcing layer is used.
H'has a trapezoidal shape in which the upper bottom L2, which is the lower side of FIG. 3, is short, and the lower bottom L1 is long. When winding is started from this longer lower bottom L1, the first layer is as shown in FIG. Is long in the axial direction and short in the second layer. Therefore, even if the reinforcing layer 12H is present, the main body layer 10J is not changed so as to be changed suddenly and is gradually changed, so that the reinforcing fibers of the main body layer 10J are less likely to be disturbed and less likely to be bent.

In the present invention, the prepreg 12 corresponding to the reinforcing layer is used.
H'is formed in a trapezoidal outer shape, and is also formed in an inclined shape so that the end region 12K located inward in the axial direction of the rod tube is gradually reduced toward the inner side. Reinforcing fiber 12
Since S is oriented in the direction shown in FIG. 3 (the direction oriented in the circumferential direction after winding), the prepreg 12 corresponding to the reinforcing layer is formed.
It is easy to form H ′ by pressing the end region 12K with an appropriate mold when forming H ′. In this way, the prepreg 12H ′ whose end regions have been press-molded in advance is superposed on the prepreg for the main body layer, wound, pressurized and heat-molded, as shown in FIG. The length L in the axial direction of the end region 12K needs to be equal to or larger than the layer thickness t of each reinforcing layer near the open end, and preferably double or more. Due to the presence of this inclined portion, the disturbance of the reinforcing fibers of the main body layer is reduced, and the bending of the molding rod tube 10 is prevented.

The thickness of the inclined portion may be reduced linearly or curvilinearly. Further, if the resin ratio of the prepreg 12H ′ corresponding to the reinforcing layer is high, the reinforcing fibers 12S will flow together with the resin and be molded by applying a high pressure at the time of heat molding without forming such an inclined portion in advance, and the end region. Can be formed in an inclined shape. Furthermore, when the amount of reinforcing fibers oriented in the axial direction is small compared to the amount of reinforcing fibers oriented in the circumferential direction (that in the axial direction relative to the thickness of the prepreg of the reinforcing fibers oriented in the circumferential direction is 1/2, or 1 /
(For thin prepregs with a thickness of 3 or less), the reinforcing layer 12
Reinforcing fibers oriented in the axial direction may be present on the outer side or the inner side of H, but it is preferable not to be present in the middle portion in the thickness direction because the inclined end portion can be easily formed.

In the above description, the reinforcing layer 12H is the main body layer 10J.
Although it is present inside or between layers, in order to prevent the meandering of the reinforcing fibers of the main body layer, the reinforcing layer may be arranged only on the outer side of the main body layer. It is preferable to use a prepreg having a thickness smaller than that of the prepreg arranged on the outside.

Next, FIG. 4 is a view showing a method of forming the rod tube 18 as the tubular body having the three-layer structure shown in FIG.
A thin inner layer 2 of reinforced fiber wound in the direction 0
6 '(FIG. 5) on top of the prepreg 2 corresponding to the thick middle layer 22' of reinforcing fibers in the axial direction.
2 shows a winding method when winding 2 and winding the prepreg 24 corresponding to the thin outer layer 24 ′ of the reinforcing fiber in the substantially circumferential direction. The rectangular prepreg 24 is shown in FIG.
Incline and wind. This outer layer prepreg 24
Is usually wound in one or two layers, and is cut so that the winding start end portion and the winding end portion are substantially overlapped, that is, approximately an integral number of turns. Therefore, the overlap line area JR
Are spirally formed on the surface of the rod tube.

As a result, the overlapping portion line JR, which can be said to be a singular point portion line in which the winding start end portion and the terminating end portion of the prepreg overlap, is not located at the specific position of the circumferential angular position but around the entire circumference of the rod tube 18. Since it exists, the factors that cause the bending of the rod tube are balanced in the circumferential direction, and the molding bending is prevented. Therefore, the spiral is about 1 around the rod tube 18.
It is preferable that the number of windings is about an integral number of turns such as one turn and two turns.
In FIG. 4, when the prepreg 24 is wound, the prepreg 24 is cut so that the reinforcing fibers 24S are inclined with respect to the axial direction of the rod tube 18, but the prepreg 24 is oriented in the circumferential direction after winding. May be cut into pieces. Further, the inner layer 26 'of the rod tube 18 is also the same as the outer layer 24', and it is preferable to similarly form the overlapping portion line in a spiral shape.

When the overlapping portion lines of both the inner layer and the outer layer are formed in a spiral shape, it is possible to further prevent the bending by forming them so that they are spirally wound in opposite directions. When only one side is formed in a spiral shape, the outer layer has a greater effect on bending, and therefore the overlapping portion JR of the outer layer is formed in a spiral shape. It is necessary to overlap the winding start end and end of the outer or inner layer,
The overlap margin is set to about 0.5 to 5 mm, but the rod tube 1
Adjust by the diameter of 8. The lap of the prepreg is not necessarily required in the middle layer of the axial length direction reinforcing fiber, but it is set so that there is almost no gap between the winding start end and the winding end. When stacking, keep it within a few millimeters.

The resin ratio of the prepreg corresponding to the middle layer 22 'is 10 to 25% by weight, preferably 10 to 20% by weight, and that of the inner layer and the outer layer is about 5 to 15% than that of the middle layer.
Increase the amount. This is preferable because resin accumulation is unlikely to occur. As described above, the sheet-shaped prepreg is used to incline and wind, and the reinforcing fiber is along the length direction of the tape, and the prepreg of the thin tape of uniform thickness is formed on the adjacent side of the wound tape. Even if it is continuously wound from one end to the other end so that the edges are coincident with each other, the overlapped portion line in the axial direction does not occur, and molding bending can be prevented. Further, even when the side edges are continuously polymerized in the winding of the tape, the superposition line which is the singular point part line has a spiral shape, so that molding bending is also prevented.

In the normal winding of tape, due to the taper change of the rod tube, the openings between the tapes and the overlapping portions, the thick portions and the thin portions are irregularly formed, and the reinforcing fibers in the axial direction also meander. Therefore, bending of the molding is likely to occur.

Generally, when the resin ratio of the prepreg corresponding to the layer of axial lengthwise reinforcing fibers is large or the winding pitch of the tightening tape is large, the axial lengthwise reinforcing fibers of this layer tend to meander. Therefore, a method of forming a tubular body by reducing the resin ratio of the axial length direction reinforcing fiber layer prepreg and reducing the winding pitch of the tightening tape will be described. In FIG. 6, mainly composed of reinforcing fibers wound around a cored bar 20 and oriented in a substantially circumferential direction,
Outside the prepreg 34 of the inner layer having a larger impregnated resin ratio than the prepreg 32 of the axial length direction reinforcing fiber layer, mainly has reinforcing fibers 32S oriented in the axial direction, and the impregnation ratio of the resin is 10 to 23% by weight. (Preferably 10 to 20% by weight)
The prepreg 32 of the axial length direction reinforcing fiber layer having a wall thickness of 75% or more of the wall thickness of the tubular body is wound, and the prepreg 32 is tightened from the outside with a tightening tape and heat-molded. When the winding pitch P of this tightening tape is set to 1.3 mm or less, preferably 1 mm or less, the reinforcing fibers 32 of the layer 32 are
The meandering of S can be prevented, and bending of the molding can be prevented. Further, the pitch P may be 1.5 mm or less if there is a layer mainly composed of reinforcing fibers oriented in the substantially circumferential direction outside the layer 32.

On the outer side of the layer 32 of a tubular body such as a rod pipe, the resin J which has flowed into the gap with the tightening tape is formed in a sawtooth shape, and this convex portion is ground flat or curved. Or, in the state where it is left as it is, paint is further applied to the outside to smooth the surface of the tubular body. It is in the case of a thick-walled rod tube, a rod tube of a small diameter, etc. that a layer of circumferential reinforcing fibers is not required outside the layer 32. The former does not require a layer of circumferential reinforcing fibers on the inside, but the latter should be present on the inside.

FIG. 7 shows a rod tube as an example of a tubular body.
The cored bar 40 shown in FIG.
And a front thin intermediate portion 44 having a large taper and a rear portion 46 having almost no taper. Front part 42 and middle part 4
4, a fiber having a large taper ratio is likely to be twisted in the axial direction to be wrinkled at a portion where the taper rate changes greatly, such as a boundary portion with 4 or a middle portion and a rear portion 46. This is because even before the reinforcing fiber of the prepreg wound around the core bar is not disturbed before heating,
The resin is flowed by the heat molding, and the reinforcing fiber is also flowed with the flow of the resin, and it tends to be disturbed particularly in a portion where the taper rate is greatly changed, and thus wrinkles are formed.

In order to prevent this, an auxiliary prepreg 48 whose axial length is shortened is used to reduce the resin impregnation ratio (10 to 20% by weight) to reduce the resin flow, and to compare with the main body prepreg 50. By reducing the resin ratio of the auxiliary prepreg 48, and the reinforcing fibers are arranged so as to be oriented mainly in the axial length direction. With the axial length direction reinforcing fibers, a minute unevenness state in the circumferential direction is created, and Friction makes it difficult for the prepreg to move in the circumferential direction, and due to the friction with the minute irregularities, the main body prepreg 50 wound on this prepreg.
The auxiliary prepreg 48 for preventing the reinforcing fibers of (1) from flowing in the circumferential direction is wound around the surface of the cored bar 40, and the main body layer prepreg 50 is wound thereon. In this way, the bending of the rod tube due to heat molding is prevented. Although not shown in FIG. 7, similar ideas may be applied to the boundary portion between the intermediate portion 44 and the rear portion 40.

[0021]

As is apparent from the above description, according to the present invention, if the reinforcing fibers of the reinforcing layer are oriented substantially in the circumferential direction of the tubular body, the wall thickness of the end region of the reinforcing layer is gradually reduced. It is easy to make the cross-sectional state change suddenly near the boundary where the prepreg of the reinforcing layer and the prepreg of the main body layer where the wall thickness of the end region located on the inner side of the tubular body is gradually reduced is overlapped. Therefore, the reinforcing fibers of the main body layer are not easily twisted, and bending of the tubular body is prevented. In this way, a high-quality tubular body can be provided at low cost.

[Brief description of drawings]

FIG. 1 is a side view of a rod tube as a tubular body according to the present invention.

FIG. 2 is an enlarged vertical cross-sectional view of portion B of FIG.

FIG. 3 is a schematic perspective view of the reinforcing layer prepreg shown in FIG. 2.

FIG. 4 is a diagram in the middle of manufacturing a tubular body according to another embodiment of the present invention.

5 is a partially cutaway side view of the tubular body formed according to FIG.

FIG. 6 is a diagram in the process of manufacturing a tubular body of another embodiment according to the present invention.

FIG. 7 is a diagram in the process of manufacturing a tubular body according to another embodiment of the present invention.

[Explanation of symbols]

 10J Main body layer 12H Reinforcing layer 12K Inner side end region

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display location B32B 1/08 B32B 5/00 B 5/00 5/12 5/12 A01K 87/00 630A // B29K 105: 08 B29C 67/14 C B29L 23:00

Claims (1)

[Claims] 1. A tubular body made of synthetic resin as a matrix and reinforced with reinforcing fibers, the tubular body being disposed in the vicinity of the end portion of a main body layer continuous from the inner portion to the end portion in the axial direction of the tubular body. And has mainly reinforcing fibers oriented substantially in the circumferential direction, and the inner end side end region has a wall thickness in the axial length direction equal to or larger than the wall thickness dimension near the other end side. A tubular body comprising a reinforcing layer which is gradually reduced in the direction of the inner portion.