JPH08207166A - Tubular body and manufacture thereof - Google Patents

Abstract

PURPOSE: To manufacture a tubular body having a light weight and a high strength by a method wherein thin layers corresponding to reinforcing layers and prepared by impregnating reinforcing fibers with a thermosetting synthetic resin are formed on layers corresponding to a main body and prepared by impregnating carbon fibers with the thermosetting synthetic resin and winding round, and they are pressed by a tightening body from outside and heated. CONSTITUTION: Carbon fibers are impregnated with a thermosetting synthetic resin and an area PA being poor in the amount of the resin and an area RA being rich in it are provided in the direction of thickness, while the average amount of the thermosetting synthetic resin for impregnation is made a value of 10 to 20wt.% approximately. The carbon fibers are wound round so that they are directed practically in the longitudinal direction of a core, and thereby a main-body layer 12 is formed so that the area RA being rich in the amount of the resin is made to face a layer on one side, at least, out of adjacent layers at the boundaries of the wound layers. Then, a prepreg prepared by impregnating reinforcing fibers with the thermosetting synthetic resin is wound round so that the main fiber directions intersect the carbon fibers directed practically in the longitudinal direction, so as to form thin reinforcing layers 14 and 16. The reinforcing layers 14 and 16 and the main-body layer 12 are pressed by tightening from outside and heated and thereby a tubular body can be manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tubular body mainly formed by winding a prepreg in which carbon fibers aligned in one direction are impregnated with a thermosetting resin and heat-pressing the prepreg to form the tubular body. . Therefore, it can be used for a rod pipe of a fishing rod, a shaft of a golf club, and the like.

[0002]

2. Description of the Related Art A fishing rod is required to be held for a long time, and is required to be light in weight from the viewpoint of improving its operability. Further, it is also required to improve its strength in order to receive a large bending force due to strong pulling by fish. Also, the golf club is light and
High strength properties are required. As described above, a fishing rod, a shaft of a golf club, and the like are required to have the contradictory performances of being lightweight and having high strength. For this reason, conventionally, a high-strength and lightweight fiber such as carbon fiber is used to form a prepreg impregnated with a synthetic resin such as an epoxy resin, and the prepreg is wound and heated under pressure. Forming a lightweight and high strength tubular body.

In this case, the weight percentage of the resin in the prepreg is generally 35% to 40%.
-44492. Further, the invention according to this publication discloses the resin impregnated amount of the first prepreg of the innermost layer of the rod tube and the resin of the second prepreg for the main body layer of the outermost layer thereof from the viewpoint of compatibility with the core metal and adhesion of each layer. It defines the relationship with the amount of impregnation, and discloses that the innermost layer has a content of 50% or less than the outer layer and the outer layer has 33% or less.

[0004]

However, since the resin amount disclosed in the above publication is too much and heavy for the fiber, and the resin amount is large as a whole, the resin layer and the resin which are easily delaminated or cracked It has been observed by photomicrographing by the Applicant that puddles (areas with no or extremely few fibers) are formed. In addition, resin flow occurs during molding, and along with this, the fibers also tend to move, and meandering and uneven distribution of the fibers occur, and strength deterioration and bending are likely to occur.

Particularly, the resin amount of the prepreg for the main body layer is 25
If it exceeds about wt%, when it is wound and tightened with a tape and then heat-molded, the prepreg material is displaced in the circumferential direction during the molding depending on the tightening condition, and many molding defects occur. However, if a prepreg impregnated with a small amount of resin on average is used, the adhesiveness at the boundary of the winding layer deteriorates, and voids occur at this boundary, especially the prepreg winding of fibers oriented in the longitudinal direction of the core metal. At the boundary between layers, the voids are likely to be continuous in the longitudinal direction, which causes a decrease in strength due to peeling.

Therefore, the present invention provides a lightweight and high-strength tubular body and a method for producing a tubular body, wherein a main body layer is formed of a prepreg in which carbon fibers are impregnated with a thermosetting synthetic resin while preventing defective molding. For the purpose of provision.

[0007]

In view of the above-mentioned object, the present invention relates to claim 1 in which carbon fiber is impregnated with a thermosetting synthetic resin to form a resin amount poor region and a resin amount rich region in the thickness direction. And a prepreg having an average impregnated amount of the thermosetting synthetic resin within a range of approximately 10 wt% to 20 wt% is used, and the direction of the carbon fibers is set to be substantially the longitudinal direction of the cored bar. At the boundary of the wound layer and the wound layer, at least one of the adjacent layers is wound so as to face the resin-rich region so as to form a thick main body layer corresponding layer and thermoset to the reinforcing fiber. Prepreg impregnated with a synthetic resin is wound so that the main fiber direction intersects with the carbon fibers oriented substantially in the longitudinal direction to form a thin reinforcing layer corresponding layer, and the reinforcing layer corresponding layer and the main body layer. Corresponding layer from outside with a tightening body Pressed and heated, to provide a method of manufacturing a tubular body, characterized in that to produce a tubular body by removing the metal core and clamping member. Here, wt% shows the weight percentage with respect to the total weight of the fiber and the resin. The reinforcing layer-corresponding layer may be located inside or outside the main body layer-corresponding layer as well as in the main body layer-corresponding layer. That is, for example, a method of manufacturing a tubular body having a main body layer in which a layer of fibers in a substantially longitudinal direction and a thin layer (a backing layer) having fibers in a substantially circumferential direction are alternately arranged is also included.

Further, according to a second aspect of the present invention, carbon fibers formed by winding a sheet-like prepreg and heating it under pressure and using thermosetting synthetic resin as a matrix and aligned so as to be oriented substantially in the longitudinal direction. The carbon fiber has a main body layer that is reinforced as a main component and has an average amount of the synthetic resin in the range of approximately 10 wt% to 20 wt%, and a resin pool is eliminated in the vicinity of the polymerized end position of the sheet-like prepreg. And a thermosetting synthetic resin.

Further, in claim 3, in each layer in which a prepreg in which carbon fiber is impregnated with a thermosetting synthetic resin is wound and cured by heating, the ratio of the thermosetting synthetic resin is unevenly distributed in the thickness direction within the layer. Provided is a tubular body characterized in that the underlying layer is the main body.

[0010]

According to the first aspect of the present invention, the prepreg has a region where the amount of resin is poor and a region where the region is rich in the thickness direction, but the average value is within the range of 10 wt% to 20 wt%, Further, since the layer corresponding to the reinforcing layer is thin, the absolute amount of resin is small, and the prepreg material is less likely to be displaced. Further, at the boundary of the wound layer, at least one layer faces the surface of the region rich in the amount of resin, so that the adhesiveness of the boundary of the wound layer becomes good, and the occurrence of voids at the boundary is prevented. Since the absolute amount of resin is small, the occurrence of resin accumulation is also prevented. Therefore,
Since the amount of resin is small, a lightweight and highly elastic tubular body with high strength is formed. Especially specific strength (strength per unit weight)
Is improved.

According to the second aspect of the invention, in the case of a tubular body formed by winding a sheet-like prepreg, resin accumulation is likely to occur near the polymerized end of the sheet-like prepreg and the tubular body is largely bent or compressed. When deformed, cracks generally occur from the resin pool portion at the polymerized end, but since the amount of synthetic resin in the main body layer is generally within the range of 10 wt% to 20 wt%, there is no excess synthetic resin and The formation of pools is prevented, the generation of cracks is suppressed, the strength is improved and the weight is light.

According to the third aspect, when the ratio of the thermosetting synthetic resin is unevenly distributed in the thickness direction in the layer, a relatively large amount of the synthetic resin is distributed to a necessary portion of each layer, which is unnecessary. Since it can be distributed in a small amount to the part,
The amount of synthetic resin can be reduced as a whole, and a lightweight and high-strength tubular body can be obtained.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail based on the embodiments shown in the accompanying drawings. FIG. 1 is a partial sectional view of a laminated tubular body 10 according to the present invention. The tubular body 10 is a sheet-shaped prepreg obtained by impregnating a bundle of carbon fibers aligned in one direction with an epoxy resin, and an appropriate number of carbon fibers are oriented in the longitudinal direction of the tubular body 10. It has a main body layer 12 which is wound and wound under pressure.
The epoxy resin is an example of the thermosetting synthetic resin, and may be a polyester resin, a phenol resin, or the like.

Reinforcing layers 14 and 16 which are thinner than the main body layer 12 are formed inside and outside the main body layer 12, respectively. Each of the reinforcing layers 14 and 16 is a prepreg obtained by impregnating carbon fiber bundles aligned in one direction with an epoxy resin so that the main direction of the fibers is in the substantially circumferential direction of the tubular body 10. It is wound and treated with the main body layer 12 under pressure and heating to cure,
The tubular body 10 is formed. The direction of carbon fibers of the main body layer 12 is the longitudinal direction of the tubular body, but a reinforcing layer mainly composed of fibers in the direction intersecting with this direction, for example, the circumferential direction described above, is mixed in the winding layers oriented in the longitudinal direction. You may let me.

The sheet-like prepreg can be molded by, for example, handling a film of thermosetting synthetic resin along one side of a bundle of aligned carbon fibers TS, or by treating both sides of the carbon fiber bundle. It is made by inserting a thermosetting synthetic resin film between a pair of rollers and pressing the same in the case of the former. In the former case, a single cross section of the prepreg is schematically shown in FIG. Like
In the latter, it becomes like (b). That is, (a) has a relatively large amount of epoxy resin as a thermosetting synthetic resin, and a resin amount rich region RA of an amount capable of preventing the generation of voids by heating and curing the resin impregnated state is present on one surface side. However, there is a small amount of resin on the other surface side, and the amount of resin is the amount of voids that will be generated if the resin is impregnated and cured by heating.
In the meanwhile, the intermediate resin amount area MA between the two is provided, and on the other hand, in (b), the resin amount rich area RA is present on both sides, the middle is the resin amount poor area PA, and the intermediate area is the resin amount intermediate area MA. It indicates that there is.

As shown in the figure, the arrangement of the carbon fibers TS in the resin amount poor area PA is mainly triangular, and the arrangement of the carbon fibers TS in the resin rich area RA is mainly square. If the cross-sectional shape of the fibers is circular and of the same size, the triangular arrangement provides the minimum amount of resin, and the square arrangement allows more impregnation. In the present invention, the average impregnated amount of the synthetic resin of the prepreg thus formed is set to a value within the range of approximately 10 wt% to 20 wt%,
Compared with the conventional type, the number is much smaller. This produces an effect such as the prevention of resin accumulation described later.

Of the adjacent wound layers sandwiching the boundary, at least one layer is wound so that the resin-rich region RA faces the boundary, and the sheet-like prepreg is wound a suitable number of times, and the body is heated and pressurized. A layer corresponding to the main body layer to be the layer 12 is formed, and the tubular body 10 is formed by heat curing treatment while applying pressure together with the layers corresponding to the reinforcing layers 14 and 16 inside and outside this layer. Of these reinforcing layers, the resin amount of the inner reinforcing layer 14 is the main layer 1
It may be set to the same level as 2, and in the outer reinforcing layer 16, when pressure is applied by the tightening tape, an air pocket due to tape polymerization remains between the tightening tape and the reinforcing layer 16, so Body layer 12 for discharging
The resin is impregnated in a larger amount than that. The reinforcing layer may have only one of the inner side and the outer side due to the necessity of reinforcement, and may have a form of being arranged between the winding layers in the main body layer 12.

In the corresponding layer of the main body layer formed as described above, the amount of resin is small, and there is a concern about poor adhesion at the boundary of each winding layer. However, in the present invention, the amount of resin is not sufficient in each winding layer. Uniformity is provided, and at least a layer on one side faces the rich region RA at the boundary, so that adhesion can be secured. Further, there is no problem that the resin moves from the rich region RA to the poor region PA at the time of pressurizing and heating, and that some small voids remain. Furthermore,
Although the amount of resin is large in the corresponding layer of the outer reinforcing layer 16,
Since this layer is thin, the absolute amount of resin is small, and it is used for eliminating air pockets by the tightening tape, so that it cannot almost move to the inside of the layer corresponding to the main body layer, and only penetrates into the adjacent contact area. Even when the resin amount of the inner reinforcing layer 14 is increased, since it is a thin layer, the absolute resin amount is small and it penetrates into the adjacent contact region. The same applies when the reinforcing layer is provided between the winding layers in the main body layer. As described above, in the present invention, the amount of the resin is appropriate, it is possible to prevent the displacement, meandering, and uneven distribution of the fibers, and further, the weight is good, and the adhesion of the winding layer boundary is improved, resulting in defective molding. It is difficult to improve the specific strength of the tubular body.

In addition to this, it is effective in preventing the resin pool J described below. That is, FIG. 3 is a diagram schematically showing a cross section of a tubular body formed by winding a prepreg having a conventional resin amount after pressure heating and curing, and an inner reinforcing layer 14 ′,
A main body layer 12 ′ and an outer reinforcing layer 16 ′, and the main body layer 12 ′ includes a layer 12A formed of an inner first sheet-like prepreg and a layer 12B formed of an outer second sheet-like prepreg. have. In such a case, the winding start end and the winding end end of each sheet-like prepreg are superposed, and in the superposed end region, the resin pool J is apt to be generated from the past and is often peeled from this. FIG. 4 is an enlarged view of this overlapping end region, and the resin pool J has almost no fibers TS and the thermosetting synthetic resin occupies most of it.

Corresponding to FIG. 4, the polymerized end region of the main body layer formed by using the sheet-like prepreg having the resin amount according to the present invention has no resin pool as shown in FIG. 5, and carbon fiber TS is suitable. Disperse into. As described above, according to the present invention, the occurrence of resin accumulation is prevented and the strength of the tubular body is improved.

Further, if a tubular body is formed by heating using a prepreg in which the synthetic resin proportions are unevenly distributed in the thickness direction as shown in FIG. 2, each winding layer obtained by heating and curing each winding layer is changed even if the proportion changes. An uneven distribution of the synthetic resin ratio remains in the thickness direction of the rotation forming layer. For example, FIG. 6 of an enlarged view of part A of FIG.
As shown in FIG. 3, three winding layers forming the main body layer 12 are rich regions RA on one side and poor regions PA on the other side. As shown in the above, if the prepregs are aligned in the same direction and stacked, the adhesion at each layer boundary improves,
The amount of resin can be reduced as a whole and weight reduction can be achieved as compared with the case of a uniform resin ratio. Therefore, the specific strength is also improved.
The resin ratio of the reinforcing layers 14 and 16 inside and outside of this embodiment is substantially uniform in each layer, and is set to be equal to or higher than the resin ratio of the rich region RA of the main body layer 12.
The boundary with 2 is prevented from causing a resin shortage and has good adhesion moldability. Further, the reinforcing layer is set thin, the absolute amount of resin is small, and it does not go against the weight reduction of the tubular body as a whole.

FIG. 7 is an enlarged view of part A of another embodiment of FIG.
Then, the body layer 12 is composed of two layers, and the rich regions R are
A is made to face. Also in this embodiment, each reinforcing layer 1
The resin ratios of Nos. 4 and 16 are substantially uniform in each layer, and are set to be equal to or higher than the resin ratio of the rich region RA of the main body layer 12. Therefore, the resin shortage is prevented even at the boundary with the main body layer 12, the adhesion moldability is good, and the reinforcing layer is set thin so that the absolute amount of the resin is small and it does not go against the weight reduction of the tubular body as a whole. .

When the reinforcing layer is not provided on any surface, the resin ratio is increased on the surface side of the main body layer. By doing so, the carbon fibers oriented substantially in the longitudinal direction are protected, scratches are prevented, and a tubular body with high durability is obtained. When the main body layer is formed of one layer, if the resin ratio of the inner and outer reinforcing layers is similar, the side with the higher resin ratio of the main body layer is adjacent to the outer reinforcing layer, and the resin is applied by pressing the tightening tape. Helps push air on the surface by the flow. When the resin ratios of the inner and outer reinforcing layers are different, the side of the main body layer having the higher resin ratio is adjacent to the reinforcing layer having the lower resin ratio, and the resin is supplied to the reinforcing layer having the lower ratio.

The reinforcing fibers of the reinforcing layer intersect with the main reinforcing fibers (carbon fibers) of the main body layer which are oriented substantially in the longitudinal direction, and are usually oriented in the substantially circumferential direction. Since the fibers greatly intersect at the interface, voids are likely to occur during molding. Therefore, it is preferable that the side having a high resin ratio is configured to face the boundary side to prevent the peeling and the damage from the interface and achieve the weight reduction.

In particular, the results of experimental confirmation of the bending strength of the material required for the fishing rod tube and the shaft of the golf club are shown below. Four-point bending of a tubular specimen with an inner diameter of 10 mm and a length of 600 mm (fulcrum interval is 500 mm, load interval is 150 m
The bending strength of m) was measured. As conventional products, a main body layer prepreg made of carbon fibers aligned in one direction with an epoxy resin of 25 wt% and a backing reinforcement prepreg made of carbon fibers aligned in a direction orthogonal to the fiber direction with an epoxy resin of 40 wt% ( The prepreg of the main body layer (thickness of about 1/5) was overlapped and wound in four layers. In the product of the present invention, the resin amount of the main body layer prepreg is 20 wt%, and the lining and the like are as described above.

The thickness of each of the four test pieces molded is slightly different, but the thickness (mm), self weight (gw), breaking load (kgw), and specific strength (kgw / gw) are shown in comparison. NO. Wall thickness Self-weight Breaking load Specific strength Conventional product 1 0.63 20.13 73.8 3.67 2 0.64 20.21 75.2 3.72 3 0.64 20.31 70.6 3.48 4 0 .64 20.22 71.6 3.54 Average value 0.64 20.22 72.8 3.60 Invented product 1 0.58 19.04 73.5 3.86 2 0.59 19.08 77.0 4.04 3 0.59 19.24 75.8 3.94 4 0.59 19.12 73.5 3.85 Average 0.59 19.12 75.0 3.92

As can be seen from the above experimental results, the invention product has a higher specific strength than the conventional product. That is, it is lightweight, strong, and easy to handle. In the method for producing a tubular body of the present invention,
It should be noted that it is preferable to preheat at the softening temperature of the resin, which is not higher than the curing temperature, and keep the temperature at this temperature so that the whole is made to conform, without suddenly raising the temperature to the curing temperature. Furthermore, since the amount of resin is smaller than in the conventional case, it is preferable to increase the pressure applied to the resin during molding to improve the adhesiveness between the fibers.

Since the main body layer 12 of the tubular body 10 of the embodiment of FIG. 1 according to the present invention does not always have sufficient strength for impact strength, it is either on the outer side of the outermost reinforcing layer 16 or the main body layer. A layer of a thermoplastic resin having a good vibration absorption property may be formed directly outside the layer 12. As an example of this resin layer,
When the polyamide fiber is wound on the layer in which the prepreg is wound, and the heat treatment for curing is performed in this state, the wound polyamide fiber is softened to form a layer. . This softening may be incomplete.
In this way, the durability of the shaft of the golf club is increased.

[0029]

As is apparent from the above description, according to the present invention, since the amount of resin with respect to the amount of fiber is appropriately adjusted, the prepreg material is less likely to be displaced during molding, and defective molding can be prevented. Further, the prepreg for forming the main body layer has a different impregnation rate of the resin in the thickness direction, and at the boundary of the wound layers, at least one side layer faces the resin-rich region surface, Although the average amount of resin is small, the adhesion at the boundary of the winding layer is good, and the occurrence of voids at the boundary is prevented, and since the absolute amount of resin is small, the occurrence of resin pool is also prevented. Furthermore, the resin amount as a whole can be reduced by unevenly distributing the resin ratio in the thickness direction of each layer of the molded tubular body and increasing the resin amount only on the necessary side. Therefore, since the amount of resin is small, a lightweight and highly elastic tubular body with high strength is formed. Particularly, the specific strength (strength per unit weight) is improved.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a tubular body according to the present invention.

FIG. 2 is a diagram showing two types of cross sections of a prepreg that forms a tubular body.

FIG. 3 is a schematic view of a cross section of a conventional tubular body.

FIG. 4 is an enlarged view of an overlapping end portion corresponding to FIG.

FIG. 5 is an enlarged view of an overlapping end portion of a tubular body main layer according to the present invention.

FIG. 6 is an enlarged view of an embodiment of part A of FIG.

FIG. 7 is an enlarged view of another embodiment of part A of FIG.

[Explanation of symbols]

 10 Tubular body 12 Body layer 14, 16 Reinforcing layer

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location B29C 70/16 B32B 1/08 A 5/02 B 5/14 // B29K 307: 04

Claims (3)

[Claims] 1. A carbon fiber is impregnated with a thermosetting synthetic resin, and has a resin amount poor region and a resin amount rich region in the thickness direction, and the average impregnation amount of the thermosetting synthetic resin is approximately Using a prepreg having a value within the range of 10 wt% to 20 wt%, the main direction of the carbon fiber is wound in a substantially longitudinal direction of the cored bar, and at the boundary of the wound layer, at least one of adjacent layers is wound. The layer on the side is wound so as to face the resin-rich region to form a thick main body layer corresponding layer, and a prepreg in which reinforcing fibers are impregnated with a thermosetting synthetic resin is used, and the main fiber direction is the substantially longitudinal direction. A thin reinforcing layer-corresponding layer wound so as to intersect with the carbon fibers oriented in the direction is formed, and the reinforcing layer-corresponding layer and the main body layer-corresponding layer are pressed from outside with a tightening body and heated, And removing the tightening body to produce a tubular body Method for manufacturing a tubular body according to claim Rukoto. 2. A sheet-shaped prepreg is wound and formed by heating under pressure, and a thermosetting synthetic resin is used as a matrix,
It is reinforced mainly with carbon fibers aligned so as to be oriented in a substantially longitudinal direction, and the average amount of the synthetic resin is about 10 w.
The main layer is in the range of t% to 20% by weight, and the vicinity of the polymerized end of the sheet-like prepreg is formed by removing the resin pool and mixing the carbon fiber and the thermosetting synthetic resin. A tubular body characterized by that. 3. In each layer in which a prepreg in which carbon fiber is impregnated with a thermosetting synthetic resin is wound and cured by heating, a layer in which the ratio of the thermosetting synthetic resin is unevenly distributed in the thickness direction in the layer is provided. A tubular body characterized by being the main body.