JP5113726B2 - Tubular body and manufacturing method thereof - Google Patents

Description

  The present invention relates to a method for producing a tubular body made of a fiber reinforced resin and a tubular body produced by the production method.

  In recent years, with the increase in powerless elderly people and female golfers, it has been desired to develop a golf club shaft (hereinafter also simply referred to as a shaft) that can extend a flight distance even with a slight force. In particular, the weight reduction of the shaft is considered as one of the effective means for solving this problem, and various efforts have been made.

  In terms of materials, first, in terms of materials, there is a change from steel to CFRP (carbon fiber reinforced plastic). Also, even with the same CFRP, the strength of the entire shaft is improved by improving the strength of the carbon fiber, changing the physical properties of the resin, or improving the adhesion strength between the carbon fiber and the resin. Is reduced. Further, as a structural effort, the weight of the strength improvement has been reduced by orienting or laminating fibers at an angle that improves the strength to improve the strength.

  Fiber-reinforced resin tubular bodies (hereinafter also referred to as FRP tubular bodies) are used in various applications. As a method for producing an FRP tubular body, a production method using a wrapping tape is known. In this manufacturing method, after a sheet-like FRP material is wound around a mandrel (core metal), a resin tape is wound while applying a predetermined tension. This resin tape is generally called a wrapping tape. A molding pressure is applied by the wrapping tape.

This wrapping tape is finally removed. In order to facilitate this removal, a wrapping tape with high releasability is preferable. Japanese Patent Application Laid-Open No. 2002-144439 discloses a wrapping tape whose inner surface is a woven pattern for the purpose of improving the releasability. Specifically, a wrapping tape in which a woven fabric and a resin film are integrated is disclosed.
JP 2002-144439 A

  In order to reduce the weight of the CFRP shaft, as described above, the strength of the fiber or resin or the adhesion between the fiber and the resin is increased to increase the strength of the entire shaft and reduce the weight of the strength improvement. Has been. And the weight reduction of the shaft has been achieved by those methods. However, there is a limit to the development to improve the strength and reduce the weight accordingly. On the other hand, there is no limit to the needs of golfers, and it is required to extend the flight distance as much as possible. One of the means for increasing the flight distance is the weight reduction of the shaft, and the demand for the weight reduction of the shaft is not exhausted. In order to realize this requirement, a method has been adopted in which the minimum strength necessary for the shaft is maintained, and characteristics (flex and torque) related to the shaft rigidity are sacrificed. However, the weight reduction by this method has also reached its limit, and the decrease in rigidity has also hindered the club function. It is important how to further reduce the weight while maintaining the rigidity of the shaft.

  As a means for realizing weight reduction while maintaining the rigidity of the shaft, it is conceivable to use CFRP having a high fiber content. That is, by increasing the content of fibers mainly responsible for the strength and rigidity of the tubular body as a molded product, the strength and rigidity per unit weight are increased and the weight can be reduced. However, since molding with CFRP having a high fiber content is insufficient in tackiness, it is difficult to mold and air easily enters between the fiber reinforced resin member layers. In this case, since the material itself contains a large amount of air, a large amount of air enters the entire tubular body. This air becomes a void, which can reduce the strength and durability of the tubular body.

  Thus, it is difficult to maintain strength and rigidity at the same time while reducing the weight.

  In the above-mentioned prior art wrapping tape, the elongation rate differs between the woven fabric and the resin film. Therefore, when the tension is applied, the woven fabric and the resin film are partially separated, the tape is twisted, or the tape is bent. Or the molding pressure may vary. Due to these phenomena, the surface of the FRP tubular body is likely to be non-uniform, and defective products are likely to occur or the strength is not uniform.

  By the way, a lightweight and high-strength FRP tubular body is useful in various applications. In this FRP tubular body, for example, a golf club shaft, weight reduction is desired. A lightweight golf club shaft can contribute to an increase in head speed and flight distance. In the present invention, based on a new technical idea, a manufacturing method has been found in which the molding accuracy can be improved and the void ratio of the FRP tubular body can be reduced. Improvement in molding accuracy can contribute to improvement in strength. A decrease in the void ratio can contribute to an improvement in strength. The improvement in strength can contribute to weight reduction of the shaft. In this manufacturing method, the material and the wrapping tape are different from conventional ones.

  An object of the present invention is to provide a method of manufacturing a tubular body that can effectively improve the forming accuracy and the void ratio.

  The manufacturing method of the present invention includes a step of winding a fiber reinforced resin member containing fibers and a matrix resin around a mandrel to obtain an intermediate molded body, and a wrapping tape while applying tension to the outer peripheral surface of the intermediate molded body. A winding process for winding the tape, a curing process for curing the matrix resin by heating the intermediate molded body on which the wrapping tape is wound, and pulling out the mandrel and removing the wrapping tape after the curing process. And obtaining a cured tubular body. A woven tape is used as the wrapping tape. When the fiber content of the intermediate molded body is Z1 (mass%) and the fiber content of the cured tubular body is Z2 (mass%), the difference (Z2-Z1) is 3 mass% or more and 30 mass% or less. It is. The fiber reinforced resin member includes a fiber reinforced resin member having a fiber content R1 of 50% by mass or more and 70% by mass or less.

  Preferably, the tape winding step includes a first winding step of winding a fabric tape around the outer peripheral surface of the intermediate formed body, and a second winding step of winding the resin film tape after the first winding step.

  Preferably, the tensile stress T1 applied to the fabric tape in the first winding step is 5 (Mpa) or more and 150 (Mpa) or less.

  Preferably, when the tensile stress applied to the fabric tape in the first winding step is T1, and the tensile stress applied to the resin film tape in the second winding step is T2, the ratio (T1 / T2) is 0.1 or more and 0.95 or less.

  Preferably, a silicon-based or fluorine-based coating material is provided on the inner surface of the resin film tape.

  Preferably, the curing step is performed after a first heating step in which heating is performed at a temperature of 70 ° C. or higher and 90 ° C. or lower for a period of 120 minutes or longer and 4320 minutes or shorter, and the first heating step is performed. And a second heating step of heating at a temperature below for 10 minutes to 60 minutes.

  Preferably, the tape winding step includes a first winding step of winding the fabric tape around the outer peripheral surface of the intermediate formed body, and a second winding step of winding the rubber tape after the first winding step.

  Preferably, the tensile stress T1a applied to the fabric tape in the first winding step is 5 (Mpa) or more and 150 (Mpa) or less.

  Preferably, when the tensile stress applied to the fabric tape in the first winding step is T1a and the tensile stress applied to the rubber tape in the second winding step is T2a, the ratio (T2a / T1a) Is 0.1 or more.

  Preferably, a silicon-based or fluorine-based coating material is provided on the inner surface of the rubber tape.

  Preferably, the wrapping tape is only a woven tape.

  Preferably, the tensile stress T1b applied to the fabric tape in the tape winding step is 5 (Mpa) or more and 150 (Mpa) or less.

  Preferably, the number L1 of wrapping layers of the fabric tape wound in the tape winding step is one or more layers at all points from the tip end position Tp1 of the tubular body to the butt end position Bt1 of the tubular body.

  A preferable tubular body is manufactured by any one of the above manufacturing methods. A more preferable tubular body has a void ratio Rb of 0.5% or less.

  Since the fiber content R1 of the fiber reinforced resin member is low, the molding accuracy can be improved. Further, by using the woven tape, the matrix resin is discharged in the curing step. Along with the matrix resin, voids can be discharged. According to the present invention, a lightweight and high-strength tubular body can be obtained.

  Hereinafter, the present invention will be described in detail based on preferred embodiments with appropriate reference to the drawings.

In the manufacturing method of this embodiment, a wrapping tape is used. In the following embodiments, the following three methods are employed as a method of using the wrapping tape.
(1) A woven tape and a resin film tape are used as the wrapping tape. (2) A woven tape and a rubber tape are used as the wrapping tape.
(3) Only woven tape is used as the wrapping tape.

  First, an embodiment in which a fabric tape and a resin film tape are used as a wrapping tape will be described with reference to FIGS. 1 to 4.

  FIG. 1 is a diagram for explaining a manufacturing method according to the first embodiment of the present invention. Here, a golf club shaft manufacturing method will be described as an example of a tubular body manufacturing method. In this manufacturing method, first, a mandrel 2 and a fiber reinforced resin member 4 are prepared. A typical mandrel 2 is made of a metal such as steel. The central axis of the mandrel 2 is a substantially straight line. The cross-sectional shape of the mandrel 2 is a circle. The mandrel 2 has a taper. Due to this taper, the mandrel 2 is made thinner toward one end thereof. The mandrel 2 may be partially parallel. In other words, the mandrel 2 may partially have a portion having a constant diameter. The diameter of the entire mandrel 2 may be constant.

  The mandrel 2 forms the inner surface of the tubular body. The shape of the hollow portion of the tubular body is determined by the shape of the mandrel 2. As will be described later, the mandrel 2 is pulled out in a later step. A mold release agent is preferably applied to the surface of the mandrel 2 so that this drawing is easy.

  In this embodiment, first, a process in which a fiber reinforced resin member is wound around a mandrel is performed. Hereinafter, this process is also referred to as a winding process.

  Prior to the winding step, a fiber reinforced resin member is prepared. In the present embodiment, the fiber reinforced resin member is in the form of a sheet. The fiber reinforced resin member is a prepreg 4. In this manufacturing method, a sheet-like fiber reinforced resin member is wound. This manufacturing method is also referred to as a sheet winding manufacturing method. Examples of the fiber reinforced resin member include prepreg 4 and fibers impregnated with a liquid resin. An example of a manufacturing method using this fiber is a so-called filament winding manufacturing method. This manufacturing method can also be applied to a filament winding manufacturing method.

  The prepreg 4 includes fibers and a matrix resin. This fiber is a carbon fiber. The carbon fibers of the prepreg 4 are oriented in one direction. As will be described later, this fiber may be other than carbon fiber. Carbon fiber is preferable from the viewpoint of a high-strength and lightweight tubular body. In the winding process, the matrix resin is not completely cured. Therefore, the prepreg 4 has flexibility. This flexibility allows the prepreg 4 to be wound around the mandrel 2. As will be described later, the matrix resin is not limited and is preferably an epoxy resin.

  Prior to the winding step, the prepreg 4 is cut into a desired shape. In the embodiment of FIG. 1, six prepregs 4 are used. In the embodiment of FIG. 1, sheets s <b> 1 to s <b> 6 are shown as examples of the cut prepreg 4. The prepreg 4 includes so-called angle layer sheets s1, s2, straight layer sheets s3, s5, s6, and a hoop layer sheet s4. The prepreg 4 includes full length sheets s1 to s5 provided over the entire length of the shaft, and a partial sheet s6 provided in a part of the shaft in the longitudinal direction. The specification of the prepreg 4 is not limited. The number of prepregs 4 is not limited. The shape, thickness, fiber type and the like of the prepreg 4 are not limited.

  In the winding step, the sheets s1 to s6 are sequentially wound around the mandrel 2. Prior to winding, the sheet s2 is bonded to the sheet s1. The bonded sheet group is wound around the mandrel 2. In this bonding, the sheet s2 is turned over. By this turning over, the fibers of the sheet s1 and the fibers of the sheet s2 are oriented in opposite directions. In FIG. 1, the angles are described in the sheets s1 to s6. This angle indicates an angle θ1 formed by the shaft axis direction and the fiber orientation direction.

  The sheets s1 to s6 are wound by, for example, human power. A winding machine (also called a rolling machine) may be used. The intermediate molded body 6 is obtained by the winding process. The intermediate molded body 6 is constituted by a wound prepreg 4. The cross section of the intermediate molded body 6 is formed of a spiral layer. This layer is formed by the prepreg 4.

  From the viewpoint of increasing the rigidity and strength of the tubular body, the fiber content R1 of the fiber-reinforced resin member (prepreg 4) is preferably 50% by mass or more, and more preferably 55% by mass. A prepreg having a low fiber content (a high resin content) has excellent tackiness (tackiness). Furthermore, a prepreg having a low fiber content (a high resin content) is flexible. A prepreg having a small fiber content R1 is easy to wind. In a prepreg having a low fiber content R1, winding defects such as wrinkles are unlikely to occur. The intermediate molded body having a winding failure is cured as it is in the curing step. A winding failure means a molding failure. From the viewpoint of increasing molding accuracy, the fiber content R1 is preferably 70% by mass or less, and more preferably 65% by mass or less. The fiber content R1 is determined in each of the cut prepregs. In the embodiment of FIG. 1, the fiber content R1 is determined for each of the sheets s1, s2, s3, s4, s5, and s6. It is sufficient that the fiber content R1 of at least one sheet satisfies the above preferable range. In some fiber-reinforced resin members, the fiber content R1 may exceed 70% by mass. The fiber content R1 can be determined based on the product data of the fiber reinforced resin member (prepreg).

  When the fiber content R1 is small (the resin content is large), the fiber content Z1 (described later) tends to be small. When the fiber content Z1 is small, the matrix resin that moves to the fabric tape during the curing process tends to increase. That is, when the fiber content R1 is small, the difference (Z2−Z1) described later tends to increase. When the matrix resin that moves to the fabric tape increases, the bubbles that move to the fabric tape together with the matrix resin tend to increase. Therefore, when the difference (Z2−Z1) is large, the void ratio tends to decrease. Moreover, when the difference (Z2-Z1) is large, the tubular body is reduced in weight. Also from these viewpoints, the fiber content R1 is preferably equal to or less than 70% by mass, and more preferably equal to or less than 65% by mass.

  In the production process of a fiber reinforced resin member (prepreg), a matrix resin is impregnated into carbon fibers aligned in one direction. When the ratio of carbon fibers is large, air easily enters in the production process of the fiber reinforced resin member. Conversely, when the ratio of the matrix resin is large, it is difficult for air to enter in the production process of the fiber reinforced resin member (prepreg). For this reason, when fiber content rate R1 is small, the void contained in a fiber reinforced resin member is comparatively few. When the fiber content R1 is large, the voids included in the fiber reinforced resin member are relatively large. Also from this viewpoint, the fiber content R1 is preferably equal to or less than 70% by mass, and more preferably equal to or less than 65% by mass.

The content rate Rx of the fiber reinforced resin member in which the fiber content rate R1 is in the preferred range is not limited. From the viewpoint of further improving the advantages obtained when the fiber content R1 is set in a preferable range, the content Rx is preferably 20% by mass or more, more preferably 30% by mass or more, and more preferably 40% by mass or more. The content Rx may be 100% by mass. When the total mass of the fiber reinforced resin member (prepreg) in which the fiber content R1 is within the above preferable range is W1 (g) and the mass of the intermediate molded body is W2 (g), the content Rx is Calculated by the formula. The mass W2 is equal to the total mass of all the fiber reinforced resin members (prepreg).
Rx = (W1 / W2) × 100

  In the curing step, the matrix resin and voids are discharged to the outside of the shaft (textile tape side). Therefore, voids existing outside the shaft are easily discharged to the outside. On the other hand, voids existing inside the shaft are not easily discharged to the outside. From this viewpoint, when a void exists, the position of the void is preferably close to the outside of the shaft.

  Hereinafter, a portion formed by the fiber reinforced resin member having the fiber content R1 in the above preferable range is m1, and the thickness of the portion m1 is tm1. Moreover, the part formed with the fiber reinforced resin member which has more fiber content rate R1 than the fiber content rate R1 of the said preferable range is set to m2, and the thickness of this part m2 is set to tm2. The thickness tm1 and the thickness tm2 are values in the cured tubular body.

  When the content rate Rx is not 100%, the part m1 and the part m2 are mixed. From the viewpoint of allowing voids to exist outside the shaft and facilitating the removal of the voids, it is preferable that the part m1 is disposed inside the part m2. From the viewpoint of facilitating void removal, the portion m2 preferably includes an outermost layer. The outer surface of this outermost layer is the outer surface of the cured tubular body.

  From the viewpoint of decreasing the void ratio, the ratio (tm1 / tk) of the thickness tm1 to the thickness tk of the cured tubular body is preferably 0.3 or more, more preferably 0.4 or more, and more preferably 0.5 or more. The ratio (tm1 / tk) may be 1.0. Preferably, the thickness tk is the sum of the thickness tm1 and the thickness tm2. The thickness tk is the thickness from the inner surface to the outer surface of the cured tubular body.

  Fiber has the property of trying to be straight. The closer the orientation angle of the fiber and the shaft axial direction are to be parallel, the less the fiber is bent and the easier it is to wind. The greater the absolute value of the fiber orientation angle θ1, the greater the bending of the fiber and the more difficult it is to wind. When winding is difficult, winding defects such as wrinkles are likely to occur. Moreover, when winding is difficult to perform, it is easy to involve a void. On the other hand, as described above, when the fiber content R1 is small, winding is easy. Considering these together, even if the absolute value of the angle θ1 is large, if the fiber content R1 is small, the difficulty of winding is reduced. Even if the absolute value of the angle θ1 is large, it is difficult to entrain the void if the fiber content R1 is small. Thus, the hardening due to the small fiber content R1 can be manifested when the absolute value of θ1 is large. From this viewpoint, the absolute value of the angle θ1 of the fiber reinforced resin member in which the fiber content R1 is in the above preferable range is preferably 20 degrees or more, more preferably 30 degrees or more, and more preferably 40 degrees or more. The upper limit of the absolute value of θ1 is 90 degrees.

  From the viewpoint of shaft strength, when the fiber of the fiber reinforced resin member is a carbon fiber, the carbon fiber is preferably a PAN system rather than a pitch system.

  Next, a tape winding process is performed. In this tape winding step, a wrapping tape is wound around the outer peripheral surface of the intermediate molded body 6. 2 and 3 are partially sectional perspective views showing a state of the tape winding process. 2 and 3, the intermediate molded body 6 is simply shown as a single layer. Actually, the intermediate molded body 6 is composed of a plurality of layers as described above.

  In the tape winding process, two types of wrapping tapes 8 and 10 are used. The first wrapping tape is a fabric tape 8. The second wrapping tape is a resin film tape 10.

  The tape winding process includes a first winding process and a second winding process. In the first winding step, the fabric tape 8 is used. The fabric tape 8 is a tape based on a fabric. In the second winding step, the resin film tape 10 is used. The resin film tape 10 is a tape having a resin film as a base material. A second winding step is performed after the first winding step. The state of the first winding step is shown in FIG. The state of the second winding step is shown in FIG.

  In the first winding step, the fabric tape 8 is directly wound around the outer peripheral surface of the intermediate molded body 6. The outer peripheral surface of the intermediate molded body 6 and the fabric tape 8 abut. The fabric tape 8 is in contact with the outer peripheral surface of the intermediate molded body 6.

  As shown in FIG. 2, in the first winding step, the fabric tape 8 is wound spirally. For the purpose of spirally winding, the axial direction of the intermediate molded body 6 and the longitudinal direction of the fabric tape 8 are not perpendicular to each other. The fabric tape 8 is wound around the intermediate molded body 6 without a gap. In order to eliminate the gap, the width W1 of the fabric tape 8 is wider than the winding pitch P1. The winding pitch P1 is indicated by a double arrow in FIG. That is, the fabric tape 8 is wound in a spiral shape while a part of the width direction is overlapped. The fabric tape 8 is wound by a known lapping machine. The fabric tape 8 is wound over the entire length of the intermediate molded body 6. As a result of the first winding step, the entire intermediate molded body 6 is covered with the fabric tape 8. Note that both ends (end of winding and end of winding) of the fabric tape 8 are fixed to the intermediate molded body 6 with an adhesive tape or the like. By fixing both ends, the winding of the fabric tape 8 is not naturally unwound.

  The fabric tape 8 is wound while applying the tension F1. The intermediate molded body 6 is fastened by the fabric tape 8 by the tension F1. By wrapping the fabric tape 8, a fabric covering 12 is obtained. The fabric cover 12 is formed by covering the intermediate molded body 6 with a fabric tape 8.

  In the second winding step, the resin film tape 10 is directly wound around the outer peripheral surface of the fabric cover 12. The outer peripheral surface of the fabric covering body 12 and the resin film tape 10 come into contact with each other. The resin film tape 10 is in contact with the outer peripheral surface of the fabric cover 12. That is, the resin film tape 10 is in contact with the fabric tape 8.

  As shown in FIG. 3, in the second winding step, the resin film tape 10 is wound spirally. For the purpose of spirally winding, the axial direction of the fabric covering 12 and the longitudinal direction of the resin film tape 10 are not perpendicular to each other. The resin film tape 10 is wound around the fabric covering body 12 without a gap. For the purpose of eliminating the gap, the width W2 of the resin film tape 10 is wider than the winding pitch P2. The winding pitch P2 is indicated by a double arrow in FIG. That is, the resin film tape 10 is spirally wound while a part of the width direction is overlapped. The resin film tape 10 is wound by a known lapping machine. The resin film tape 10 is wound over the entire length of the fabric cover 12. As a result of the second winding step, the entire fabric covering 12 is covered with the resin film tape 10. In addition, both ends (end of winding start and end of winding end) of the resin film tape 10 are fixed to the fabric covering 12 with an adhesive tape or the like. By fixing both ends, the winding of the resin film tape 10 is not naturally unwound.

  The resin film tape 10 is wound while applying the tension F2. The fabric cover 12 is fastened by the resin film tape 10 by the tension F2.

  By the first winding process and the second winding process as described above, the intermediate molded body 6 is clamped by the fabric tape 8 and the resin film tape 10.

  In addition, although the spiral pattern by the fabric tape 8 is formed in the surface of the textile covering body 12, description of the spiral pattern by this fabric tape 8 is abbreviate | omitted in FIG.

  Next, a curing process is performed. In this curing step, the matrix resin is cured in the intermediate molded body 6 around which the fabric tape 8 and the resin film tape 10 are wound. This curing process is a heating process. Heating is performed by a heating furnace. An example of the heating furnace is a heating furnace using hot air. In this heating furnace, hot air is generated from the ceiling in the furnace, and this hot air circulates in the furnace. This hot air is blown to the object to be heated (intermediate molded body 6 covered with tape).

  In the curing step, since the matrix resin is heated, the matrix resin can be fluidized. Bubbles in the matrix resin can move together with the matrix resin. The fluidized matrix resin can move to the fabric tape. Bubbles in the matrix resin can also move to the fabric tape together with the matrix resin. Due to the movement (discharge) of the bubbles, the void ratio of the tubular body can be reduced.

  A preferred curing process includes a first heating step and a second heating step. More preferably, a hardening process consists only of a 1st heating step and a 2nd heating step. After the first heating step, a second heating step is performed. The temperature of the first heating step is lower than the temperature of the second heating step.

  The temperature of the first heating step is low. When the temperature is low, there is little thermal expansion of the bubbles. Since the thermal expansion is small, bubbles are difficult to increase. In the first heating step, curing of the matrix resin proceeds while suppressing thermal expansion of the bubbles. Since the curing of the matrix resin proceeds in the first heating step, the thermal expansion of the bubbles is unlikely to occur at the stage of transition to the second heating step. By setting the first heating step for a long time, the curing of the matrix resin in the first heating step further proceeds. When the matrix resin is cured by the first heating step, the thermal expansion of the bubbles in the second heating step is further unlikely to occur.

  From the viewpoint of suppressing thermal expansion of bubbles, the temperature of the first heating step is preferably 115 ° C. or less, preferably 100 ° C. or less, and more preferably 90 ° C. or less.

  From the viewpoint of fluidizing the matrix resin in the first heating step and promoting the movement of the matrix resin to the woven tape, the temperature of the first heating step is preferably 60 ° C or higher, preferably 70 ° C or higher, and 80 ° C or higher. More preferred.

  From the viewpoint of increasing the time during which the matrix resin is fluidized, the time of the first heating step is preferably 15 minutes or more, more preferably 20 minutes or more, more preferably 30 minutes or more, and more preferably 120 minutes or more. From the viewpoint of promoting the curing of the matrix resin, when the temperature of the first heating step is lower than 80 ° C., the time of the first heating step is preferably 1440 minutes or more.

  From the viewpoint of shaft productivity, the time of the first heating step is preferably 4320 minutes or less.

  Due to the long first heating step, the curing of the matrix resin has progressed considerably. However, since the first heating step is low temperature, the curing of the matrix resin is not complete. For this reason, a second heating step is set. The matrix resin can be completely cured by the high-temperature second heating step.

  From the viewpoint of promoting the curing of the matrix resin, the temperature of the second heating step is preferably 120 ° C. or higher, and more preferably 130 ° C. or higher. From the viewpoint of reducing the cost of energy required for manufacturing the shaft, the temperature of the second heating step is preferably 200 ° C. or less, and more preferably 150 ° C. or less.

  From the viewpoint of promoting the curing of the matrix resin, the time of the second heating step is preferably 10 minutes or more, and more preferably 15 minutes or more. From the viewpoint of shaft productivity, the time of the second heating step is preferably 240 minutes or less, more preferably 120 minutes or less, and even more preferably 60 minutes or less.

  The temperature of the curing process may mean the temperature of air in the heating furnace (oven). The temperature of the curing process can mean the surface temperature of the wrapping tape in the curing process.

  After the curing step, the mandrel 2 is pulled out and the wrapping tape is removed to obtain a cured tubular body. For removing the wrapping tape, the resin film tape 10 is removed first, and then the fabric tape 8 is removed. Either the drawing of the mandrel 2 or the removal of the wrapping tape may be performed first. From the viewpoint of workability, the wrapping tape is preferably removed after the mandrel 2 is pulled out.

  Usually, finishing processing is given to the above-mentioned hardening tubular body, and the tubular body of the final product is completed. This finishing process may include cutting of both ends, surface polishing, painting, and the like.

  FIG. 4 is a cross-sectional view of the resin film tape 10. The resin film tape 10 includes a base material 14 made of a resin film and a coating agent 16. The coating agent 16 forms a layer. The resin film tape 10 has a two-layer structure of a base material 14 and a coating agent 16. A coating agent 16 is provided on the inner surface of the substrate 14. The coating agent 16 is preferably a fluorine compound or a silicon compound. In addition, from the viewpoint of suppressing wrinkles generated on the fabric tape 8, a coating agent may be provided on the inner surface of the fabric tape 8.

  As described above, the resin (matrix resin) contained in the fiber reinforced resin member can be transferred to the fabric tape 8 during the manufacturing process. In particular, in the first heating step, the matrix resin easily moves to the woven tape 8.

  The fabric tape 8 has gaps and holes between the woven fibers. Therefore, the fabric tape 8 can absorb and / or transmit resin. The woven tape 8 makes it easy for the matrix resin to be discharged out of the molded body, and the fiber content of the tubular body can be improved. Along with the matrix resin, voids can be discharged. Thereby, the weight reduction of a tubular body and the fall of a void rate can be achieved.

  As a means for increasing the fiber content of the FRP tubular body, it is conceivable to use a fiber reinforced resin member having a high fiber content R1. A high fiber content R1 means a low resin content. A fiber reinforced resin member having a low resin content has low tackiness (adhesiveness). Therefore, the fiber reinforced resin member having a low resin content has low adhesion between the fiber reinforced resin members. Such a fiber-reinforced resin member having low adhesiveness is easy to be unwound once wound. In such a fiber reinforced resin member having low tackiness, it is difficult to wind the mandrel 2 and wrinkles are likely to occur during winding. That is, in a fiber reinforced resin member having a high fiber content R1, winding defects are likely to occur. Moreover, since the adhesiveness is poor when the fiber content R1 is high, air is likely to be contained between the layers of the fiber reinforced resin member layer wound in a spiral shape. This air can become a void in the tubular body. This void impairs the strength and durability of the shaft. A fiber-reinforced resin member having low adhesiveness tends to cause a decrease in productivity and a molding failure.

  In the manufacturing method of the present embodiment, the fabric tape 8 is wound around the outer side of the intermediate molded body while applying tension, and the resin film tape 10 is wound around the outer side of the intermediate molded body while applying tension. By this manufacturing method, the resin contained in the fiber reinforced resin member is absorbed by the fabric tape 8 during the curing step. By this absorption, the fiber content of the FRP tubular body can be increased without using a fiber reinforced resin member having a high fiber content R1. Therefore, the fiber content of the tubular body can be increased while using a fiber-reinforced resin member having high tackiness. Furthermore, the fabric tape 8 can also absorb or transmit air contained in the intermediate molded body 6. As a result, air that causes voids can easily escape and the strength of the FRP tubular body can be improved. Further, when the resin film tape 10 applies a large pressure to the intermediate molded body 6, air that causes voids can be more easily removed, and the strength of the FRP tubular body can be improved.

  Absorption of the resin by the fabric tape 8 is performed after winding the fiber reinforced resin member. In the present embodiment, a fiber reinforced resin member having a low fiber content R1 is used, and the fiber content of the finally obtained tubular body can be increased. In this embodiment, the fiber-reinforced resin member can be easily wound, and an improvement in the fiber content of the shaft can be achieved. In this embodiment, since the fiber content is improved during the curing step, weight reduction is achieved while maintaining moldability and productivity.

  In this embodiment, the resin film tape 10 is wound around the outer side of the fabric tape 8. The resin film tape 10 that is substantially impermeable to air and resin is wound around the outer side of the fabric tape 8, so that the resin transfer from the fiber reinforced resin member to the fabric tape 8 can be further promoted. Moreover, since the air contained in the intermediate molded body 6 can move to the fabric tape 8, an FRP tubular body in which air accumulation and voids are suppressed can be obtained.

  As described above, in the wrapping tape described in JP-A-2002-144439, the woven fabric and the resin film are integrated. In this tape, there is a possibility that the resin is absorbed by the fabric portion. In practice, however, this integrated tape has been found to have a low resin absorption effect.

  The reason why the absorption effect is low is considered as follows. The wrapping tape is wound in a spiral shape while being partially overlapped in the width direction. Therefore, the wrapping tape wound spirally has an overlapping portion where the wrapping tapes overlap each other. That is, in this overlapping portion, there is an inner wrapping tape (inner tape) in contact with the intermediate formed body and an outer wrapping tape (outer tape) located outside the inner tape. In the case of a conventional integrated wrapping tape, the resin film layer present on the inner tape is interposed between the outer tape and the intermediate molded body. This resin film layer is impermeable to resin and air. Therefore, in the case of the conventional integrated tape, the resin film layer of the inner tape inhibits the transfer of the resin and air to the fabric layer of the outer tape in the overlapping portion. As described above, in the conventional integrated tape, the resin and air hardly transfer to the fabric layer.

  Furthermore, in the tape in which the woven fabric and the resin film are integrated, since the gap between the woven fabric and the resin film is reduced, it is considered that the resin absorption effect is low. Furthermore, in the conventional integrated tape, a part of the adhesive layer existing between the woven fabric and the resin film layer penetrates into the woven fabric, and the gap of the woven fabric itself is reduced. The absorption effect of is considered to be low.

  On the other hand, in this embodiment, the fabric tapes overlap in the overlapping portion. In this overlapping portion, there is no resin tape layer inside the fabric tape. Therefore, resin and air can transfer to the entire woven tape including the overlapping portion, and the resin and air can easily transfer to the woven tape.

  Furthermore, in this embodiment, since the fabric tape 8 and the resin film tape 10 are separate bodies and both are wound separately, the gap between the fabric tape 8 and the resin film tape 10 tends to be large. Therefore, the resin and air easily move to the fabric layer.

  As described above, the fabric tape 8 is spirally wound while being partially overlapped in the width direction. Unevenness is formed by the fabric tape 8 wound spirally in this way. The thickness of the overlapping portion of the fabric tapes 8 is twice the thickness of the overlapping portion. Therefore, unevenness is caused by the overlapping portion and the non-overlapping portion of the fabric tape 8. Further, the width direction edge 9 (see FIG. 2) of the fabric tape 8 forms a step corresponding to the thickness of the fabric tape 8. Unevenness is formed by this step. These irregularities increase the gap between the fabric tape 8 and the resin film tape 10. Resin and air can enter such voids. Therefore, the resin and air easily move to the fabric tape 8 side.

  In the second winding step, the resin film tape 10 is wound around the fabric covering body 12 while being given a tension F2. Due to this tension F2, wrinkles may occur in the fabric tape 8 around which the resin film tape 10 is wound. The coating agent 16 can suppress the generation of wrinkles. The coating agent 16 can reduce the frictional resistance between the fabric tape 8 and the resin film tape 10 in the second winding step. Due to the decrease in the frictional resistance, the generation of wrinkles in the fabric tape 8 can be suppressed. Further, the coating agent 16 imparts releasability to the resin film tape 10. Due to this releasability, the resin film tape 10 can be easily removed.

  As described above, the fabric tape 8 is wound while the tension F1 is applied, and the resin film tape 10 is wound while the tension F2 is applied. Here, the tensile stress T1 applied to the fabric tape 8 in the first winding step and the tensile stress T2 applied to the resin film tape 10 in the second winding step are defined. The tensile stress T1 is a value obtained by dividing the tension F1 by the cross-sectional area S1 of the fabric tape 8. That is, [T1 = F1 / S1]. This cross-sectional area S1 is measured in the fabric tape 8 in a state where the tension is not applied (free). This tensile stress T1 means a tensile stress that acts on the fabric tape 8 immediately before winding. This tensile stress T1 does not mean the tensile stress acting on the fabric tape 8 in the wound state. The tensile stress T2 is a value obtained by dividing the tension F2 by the cross-sectional area S2 of the resin film tape 10. That is, [T2 = F2 / S2]. This cross-sectional area S2 is measured in the resin film tape 10 in a state where tension is not applied (free). This tensile stress T2 means the tensile stress acting on the resin film tape 10 immediately before being wound. The tensile stress T2 does not mean a tensile stress that acts on the resin film tape 10 in a wound state.

  From the viewpoint of increasing the amount of resin transferred to the fabric tape 8 and suppressing the sagging of the fabric tape 8, the tensile stress T1 is preferably 5 Mpa or more, more preferably 10 Mpa or more, more preferably 20 Mpa or more, and more preferably 25 Mpa or more. Preferably, 30 Mpa or more is more preferable. From the viewpoint of suppressing the level difference generated on the surface of the tubular body and suppressing the polishing amount for smoothing the surface of the tubular body, the tensile stress T1 is preferably 150 Mpa or less, more preferably 100 Mpa or less, and further preferably 60 Mpa or less.

  From the viewpoint of increasing the amount of resin transferred to the fabric tape 8, the tensile stress T2 is preferably 40 Mpa or more, more preferably 50 Mpa or more, and even more preferably 65 Mpa or more. From the viewpoint of preventing the resin film tape 10 from being cut, the tensile stress T2 is preferably 200 Mpa or less, more preferably 180 Mpa or less, and more preferably 150 Mpa or less.

  The tensile stress T2 is preferably larger than the tensile stress T1. By setting T2> T1, the amount of resin transferred to the fabric tape 8 can be increased. By making the tensile stress T1 relatively small, the gap of the fabric tape 8 is easily maintained. By making the tensile stress T2 relatively large, it is possible to increase the tightening force to the intermediate molded body 6 while maintaining the gap of the fabric tape 8. Therefore, the resin easily moves to the fabric tape 8 by T2> T1. Further, by setting T2> T1, voids in the FRP tubular body are reduced.

  From the viewpoint of suppressing generation of wrinkles on the fabric tape 8 in the second winding step, the ratio (T1 / T2) is preferably 0.1 or more, more preferably 0.2 or more, and further preferably 0.4 or more. . From the viewpoint of increasing the amount of resin transferred to the fabric tape 8, the ratio (T1 / T2) is preferably 0.95 or less, more preferably 0.9 or less, and even more preferably 0.8 or less.

  In the present embodiment, the fiber content of the intermediate molded body 6 is Z1 (mass%), and the fiber content of the cured tubular body is Z2 (mass%). From the viewpoint of weight reduction and low void ratio, the difference (Z2-Z1) is preferably 3% by mass or more, more preferably 4% by mass or more, more preferably 5% by mass or more, and further preferably 6% by mass or more. When the resin is excessively removed, the productivity tends to decrease due to difficulty in removing the wrapping tape. In this respect, the difference (Z2−Z1) is preferably 30% by mass or less, more preferably 25% by mass or less, more preferably 20% by mass or less, and further preferably 15% by mass or less.

  The manufacturing method for making a difference (Z2-Z1) 3 mass% or more and 30 mass% or less is not limited to the said manufacturing method containing a 1st winding process and a 2nd winding process. As this manufacturing method, the manufacturing method which winds only the textile tape 8 in the said winding process is illustrated. This manufacturing method is the same as the above manufacturing method except that the second winding step is not included. An example of a manufacturing method for winding only the fabric tape 8 will be described later.

  From the viewpoint of increasing the rigidity and strength of the FRP tubular body, the fiber content Z1 is preferably 50% by mass or more, and more preferably 55% by mass or more. The fiber content Z1 is preferably 70% by mass or less from the viewpoint of suppressing winding failure, from the viewpoint of reducing the amount of voids contained in the fiber reinforced resin member, from the viewpoint of reducing the void ratio of the shaft, and from suppressing variation in shaft physical properties. 65 mass% or less is more preferable. The fiber content Z1 of the intermediate molded body 6 is calculated based on the individual fiber content R1. The fiber content Z1 can be determined based on the product data of the fiber reinforced resin member (prepreg 4).

  The fiber content Z2 of the cured tubular body is not limited. From the viewpoint of reducing the weight of the FRP tubular body, the fiber content Z2 is preferably 60% by mass or more, more preferably 70% by mass or more, more preferably 75% by mass or more, and still more preferably 80% by mass or more. If the resin is excessively removed, the resin discharged from the intermediate molded body 6 makes it difficult to remove the wrapping tape, and thus the productivity is likely to be reduced. In this respect, the fiber content Z2 is preferably equal to or less than 95% by mass, more preferably equal to or less than 90% by mass, even more preferably equal to or less than 85% by mass, and still more preferably equal to or less than 83% by mass. The value of the fiber content Z2 is calculated from the value of the fiber content Z1, the mass of the intermediate molded body 6, and the mass of the removed resin. Even when the fiber content Z1 of the intermediate molded body is low, the fiber content Z2 of the cured tubular body can be increased. The resin discharge amount, that is, the difference (Z2−Z1) depends on the wrapping stress of the fabric tape, the thickness of the fabric tape, the gap of the fabric tape, and the like, rather than the fiber content Z1.

  The fibers of the woven tape 8 are preferably nylon fibers and polyester fibers in consideration of releasability, tightening force, strength, and the like. The thickness d1 of the fabric tape 8 is not limited. From the viewpoint of increasing the amount of resin absorbed by the fabric tape 8 and increasing the gap between the fabric tape 8 and the resin film tape 10, the thickness d1 of the fabric tape 8 is preferably 50 μm or more, more preferably 70 μm or more. 90 μm or more is more preferable. From the viewpoint of suppressing wrinkles and reducing the cost, the thickness d1 of the woven tape 8 is preferably 150 μm or less, more preferably 140 μm or less, and even more preferably 130 μm or less.

  The width W1 of the fabric tape 8 is not limited. From the viewpoint of increasing the amount of resin that can be absorbed by the fabric tape 8, the width W1 of the fabric tape 8 is preferably 5 mm or more, more preferably 7 mm or more, and even more preferably 10 mm or more. From the viewpoint of suppressing generation of wrinkles and facilitating tightening of the intermediate molded body 6, the width W1 of the fabric tape 8 is preferably 35 mm or less, more preferably 30 mm or less, and even more preferably 25 mm or less.

  The woven structure of the fabric tape 8 is not limited. Examples of this weave structure include plain weave, satin weave and twill weave. When it is stretched excessively by tension, the amount of resin that can be absorbed by voids and fibers in which the resin can enter easily decreases. From the viewpoint of suppressing excessive stretching due to the tension, it is preferable that the woven structure has a thread oriented substantially parallel to the longitudinal direction of the fabric tape 8.

  Examples of the material of the base material 14 of the resin film tape 10 include polypropylene resin and polyester resin. These resins are preferable because of their high tensile strength. Furthermore, a resin film tape that shrinks in a temperature range in which the viscosity of the resin in the fiber reinforced resin member decreases, for example, a composite film obtained by laminating and laminating a polypropylene resin layer and a polyester resin layer is preferable.

  The thickness d2 of the resin film tape 10 is not limited. From the viewpoint of suppressing the cutting by the tension F2, the thickness d2 of the resin film tape 10 is preferably 10 μm or more, more preferably 15 μm or more, more preferably 20 μm or more, and further preferably 25 μm or more. From the viewpoint of suppressing wrinkles and reducing the cost, the thickness d2 of the resin film tape 10 is preferably 150 μm or less, more preferably 120 μm or less, more preferably 100 μm or less, and even more preferably 50 μm or less.

  The width W2 of the resin film tape 10 is not limited. From the viewpoint of suppressing a step generated on the surface of the tubular body, the width W2 is preferably 10 mm or more, more preferably 12 mm or more, and still more preferably 14 mm or more. In light of suppressing wrinkles during winding, the width W2 is preferably equal to or less than 35 mm, more preferably equal to or less than 30 mm, and still more preferably equal to or less than 25 mm.

The fiber of the fiber reinforced resin member is not limited. As this fiber, an inorganic fiber, an organic fiber, and a metal fiber are illustrated. Examples of the inorganic fiber include carbon fiber, glass fiber, boron fiber, silicon carbide fiber, and alumina fiber. Examples of the organic fibers include polyethylene fibers and polyamide fibers. A plurality of fibers may be combined. From the viewpoint of obtaining a lightweight tubular body while ensuring the rigidity required for the golf club shaft, the tensile elastic modulus of the fiber is preferably 5 t / mm ² or more, more preferably 10 t / mm ² or more, and 24 t / mm ² or more. Is more preferable. From the viewpoint of fiber availability, the tensile elastic modulus of the fiber is preferably 100 t / mm ² or less. This tensile elastic modulus is measured according to JIS R7601: 1986 “Carbon fiber test method”.

  Next, an embodiment in which a fabric tape and a rubber tape are used as the wrapping tape will be described with reference to FIGS.

  FIG. 5 is a diagram for explaining the manufacturing method according to the second embodiment. Here, a golf club shaft manufacturing method will be described as an example of a tubular body manufacturing method. In this manufacturing method, first, a mandrel 2a and a fiber reinforced resin member 4a are prepared. The mandrel 2a is also called a cored bar. A typical mandrel 2a is made of metal such as steel. The central axis of the mandrel 2a is a substantially straight line. The mandrel 2a has a circular cross-sectional shape. The mandrel 2a has a taper. Due to this taper, the mandrel 2a is made thinner toward one end thereof. The mandrel 2a may be partially parallel. In other words, the mandrel 2a may partially have a portion having a constant diameter. The diameter may be constant throughout the mandrel 2a.

  The mandrel 2a forms a hollow portion of the finally obtained tubular body. The shape of the hollow part of the tubular body is determined by the shape of the mandrel 2a. As will be described later, the mandrel 2a is pulled out in a later step. Preferably, a release agent is applied to the surface of the mandrel 2a so that this drawing becomes easy.

  In this embodiment, first, a process in which a fiber reinforced resin member is wound around a mandrel is performed.

  Prior to the winding step, the prepreg 4a is cut into a desired shape. In the embodiment of FIG. 5, six prepregs 4a are used. In the embodiment of FIG. 5, sheets h1 to h6 are shown as examples of the cut prepreg 4a. The prepreg 4a includes so-called angle layer sheets h1, h2, straight layer sheets h3, h5, h6, and a hoop layer sheet h4. The prepreg 4a includes full length sheets h1 to h5 provided over the entire length of the shaft, and a partial sheet h6 provided in a part in the shaft longitudinal direction. The specification of the prepreg 4a is not limited. The shape, thickness, fiber type, and the like of the prepreg 4a are not limited.

  The winding process is the same as in the first embodiment. The prepreg 4a is the same as the prepreg 4 described above.

  Only the tape winding process is different between the first embodiment described above and the second embodiment. The second embodiment is the same as the first embodiment except that a rubber tape is used instead of the resin film tape.

  In the tape winding process of the present embodiment, the wrapping tape is wound around the outer side of the intermediate molded body 6a. 6 and 7 are partially sectional perspective views showing the state of the tape winding process. 6 and 7, the intermediate molded body 6a is simply shown as a single layer. Actually, the intermediate molded body 6a includes a plurality of layers as described above.

  In this tape winding process, two types of wrapping tapes 8a and 10a are used. The first wrapping tape is a fabric tape 8a. The second wrapping tape is a rubber tape 10a.

  This tape winding process includes a first winding process and a second winding process. In the first winding step, the fabric tape 8a is used. The fabric tape 8a is a tape having a fabric as a base material. The fabric tape 8a may be composed of only a fabric. In the second winding step, the rubber tape 10a is used. The rubber tape 10a is a tape whose base material is rubber or a rubber composition. The rubber tape 10a may consist only of a rubber composition. A second winding step is performed after the first winding step. The state of the first winding step is shown in FIG. The state of the second winding step is shown in FIG.

  In the first winding step, the fabric tape 8a is directly wound around the outer peripheral surface of the intermediate molded body 6a. The outer peripheral surface of the intermediate molded body 6a abuts on the fabric tape 8a. The fabric tape 8a is in contact with the outer peripheral surface of the intermediate molded body 6a.

  As shown in FIG. 6, in the first winding step, the fabric tape 8a is wound spirally. For the purpose of spirally winding, the axial direction of the intermediate molded body 6a and the longitudinal direction of the fabric tape 8a are not perpendicular to each other. The fabric tape 8a is wound around the intermediate molded body 6a without a gap. In order to eliminate the gap, the width W1a of the fabric tape 8a is wider than the winding pitch P1a. The winding pitch P1a is indicated by a double arrow in FIG. That is, the fabric tape 8a is wound spirally while a part of the width direction is overlapped. The fabric tape 8a is wound by a known wrapping machine. The fabric tape 8a is wound over the entire length of the intermediate molded body 6a. As a result of the first winding step, the entire intermediate molded body 6a is covered with the fabric tape 8a. Note that both ends (end of winding and end of winding) of the fabric tape 8a are fixed to the intermediate molded body 6a with an adhesive tape or the like. By fixing both ends, the winding of the fabric tape 8a is not naturally unwound.

  The fabric tape 8a is wound while applying a tension F1a. The intermediate formed body 6a is fastened by the fabric tape 8a by the tension F1a. By winding the fabric tape 8a, the fabric covering 12a is obtained. The fabric covering 12a is formed by covering the intermediate molded body 6a with a fabric tape 8a.

  In the second winding step, the rubber tape 10a is wound around the outside of the intermediate molded body 6a. In this second winding step, the rubber tape 10a is directly wound around the outer peripheral surface of the fabric covering body 12a. The outer peripheral surface of the fabric covering body 12a and the rubber tape 10a are in contact with each other. The rubber tape 10a is in contact with the outer peripheral surface of the fabric covering body 12a. That is, the rubber tape 10a is in contact with the fabric tape 8a.

  As shown in FIG. 7, in the second winding step, the rubber tape 10a is wound spirally. For the purpose of spirally winding, the axial direction of the fabric covering 12a and the longitudinal direction of the rubber tape 10a are not perpendicular to each other. The rubber tape 10a is wound around the fabric covering body 12a without a gap. For the purpose of eliminating the gap, the width W2a of the rubber tape 10a is wider than the winding pitch P2a. The winding pitch P2a is indicated by a double arrow in FIG. That is, the rubber tape 10a is wound spirally while a part of the width direction is overlapped. The rubber tape 10a is wound by a known wrapping machine. The rubber tape 10a is wound over the entire length of the fabric covering body 12a. As a result of the second winding step, the entire fabric covered body 12a is covered with the rubber tape 10a. Note that both ends (end of winding and end of winding) of the rubber tape 10a are fixed to the woven fabric covering body 12a with an adhesive tape or the like. By fixing both ends, the rubber tape 10a cannot be unwound naturally.

  The rubber tape 10a is wound while applying a tension F2a. The fabric cover 12a is fastened by the rubber tape 10a by the tension F2a.

  By the first winding process and the second winding process as described above, the intermediate molded body 6a is clamped by the fabric tape 8a and the rubber tape 10a.

  In addition, although the spiral pattern by the fabric tape 8a is formed in the surface of the fabric covering 12a, description of the spiral pattern by this fabric tape 8a is abbreviate | omitted in FIG.

  Next, a curing process is performed. In this curing step, the matrix resin is cured in the intermediate molded body 6a around which the fabric tape 8a and the rubber tape 10a are wound. This curing step is the same as in the first embodiment described above. As described above, this curing step preferably includes a first heating step and a second heating step.

  After the curing step, a step of drawing the mandrel 2a and removing the wrapping tape to obtain a cured tubular body is performed. For removing the wrapping tape, the rubber tape 10a is removed first, and then the fabric tape 8a is removed. Either the drawing of the mandrel 2a or the removal of the wrapping tape may be performed first. From the viewpoint of workability, the wrapping tape is preferably removed after the mandrel 2a is pulled out. On the surface of the cured tubular body, traces of the woven tape 8a wound spirally remain as spiral irregularities.

  FIG. 8 is a cross-sectional view of the rubber tape 10a. The rubber tape 10a has a base material 14a made of a rubber composition and a coating agent 16a. The rubber tape 10a has a two-layer structure of a base material 14a and a coating agent 16a. A coating agent 16a is provided on the inner surface of the substrate 14a. The coating agent 16a is preferably a fluorine compound or a silicon compound. The coating agent 16a may not be provided. Further, from the viewpoint of suppressing wrinkles generated on the fabric tape 8a, a coating agent may be provided on the inner surface of the fabric tape 8a.

  In the second embodiment, the preferred range of the fiber content R1 is the same as that of the first embodiment.

  According to the second embodiment, similar to the first embodiment, since the fiber reinforced resin member having a small fiber content R1 is used, the molding accuracy is improved and the void ratio is suppressed. In the second embodiment, the resin contained in the fiber-reinforced resin member can be transferred to the fabric tape 8a during the manufacturing process. The fabric tape 8a has gaps and holes between the woven fibers. Therefore, the fabric tape 8a can absorb and / or transmit the resin. The fabric tape 8a makes it easier for the matrix resin to be discharged to the outside of the molded body, and the fiber content of the tubular body can be improved. Along with the matrix resin, voids can be discharged. Thereby, the weight reduction of a tubular body and the fall of a void rate can be achieved.

  In the present embodiment, the fabric tape 8a is wound directly around the outside of the intermediate molded body while applying tension, and the rubber tape 10a is wound around the outside while applying tension. By this manufacturing method, the resin contained in the fiber reinforced resin member is absorbed by the fabric tape 8a during the heating step. By this absorption, the fiber content of the FRP tubular body can be increased without using a fiber reinforced resin member having a high fiber content R1. Therefore, even if a fiber-reinforced resin member having high tackiness is used, the fiber content can be increased. Furthermore, the fabric tape 8a can absorb or transmit air contained in the intermediate molded body 6a. As a result, air that causes voids can easily escape and the strength of the FRP tubular body can be improved. Moreover, since the rubber tape 10a is an elastic body, the pressure toward the center of the intermediate molded body 6a can be effectively applied. This pressure makes it easier for the matrix resin and voids to escape, and the strength of the FRP tubular body can be improved. Since the rubber tape 10a is wound in an elastically stretched state, it tends to shrink. Due to the force to shrink, the rubber tape 10a can effectively press the surface of the intermediate molded body 6a. This pressing force makes it easier for air that causes voids to escape, and the strength of the FRP tubular body can be improved. This pressing force makes it easier for the matrix resin to come out, and the FRP tubular body is reduced in weight.

  The absorption (extraction) of the resin by the fabric tape 8a is performed after winding the fiber reinforced resin member. In the present embodiment, an FRP tubular body having a high fiber content can be obtained without using a fiber reinforced resin member having excessively low adhesiveness. That is, in the present invention, the fiber-reinforced resin member can be easily wound and the fiber content can be improved. Since the fiber content is improved after the winding process, weight reduction is achieved while maintaining moldability and productivity.

  In this embodiment, the rubber tape 10a is wound around the outer side of the fabric tape 8a. The rubber tape 10a that is substantially impermeable to air and resin is wound around the outer side of the fabric tape 8a, whereby the resin transfer from the fiber reinforced resin member to the fabric tape 8a can be further promoted. Moreover, since the air contained in the intermediate molded body 6a can move to the fabric tape 8a, an FRP tubular body in which air accumulation and voids are suppressed can be obtained.

  In the present embodiment, the fabric tapes are overlapped at the overlapping portion where the wrapping tapes are overlapped. In this overlapping portion, there is no resin tape layer or rubber tape layer inside the fabric tape. Therefore, resin and air can transfer to the entire woven tape including the overlapping portion, and the resin and air can easily transfer to the woven tape.

  Furthermore, in this embodiment, since the fabric tape 8a and the rubber tape 10a are separate bodies and both are wound separately, the gap between the fabric tape 8a and the rubber tape 10a tends to be large. Therefore, the resin and air easily move to the fabric layer.

  As described above, the fabric tape 8a is wound spirally while a part of the width direction is overlapped. Unevenness is formed by the fabric tape 8a wound spirally in this way. The thickness of the overlapping portion of the fabric tapes 8a is twice the thickness of the overlapping portion. Therefore, unevenness is caused by the overlapping portion and the non-overlapping portion of the fabric tape 8a. Moreover, the width direction edge 9 (refer FIG. 6) of the fabric tape 8a forms the level | step difference equivalent to the thickness of the fabric tape 8a. Unevenness is formed by this step. These irregularities increase the gap between the fabric tape 8a and the rubber tape 10a. Resin and air can enter such voids. Therefore, the resin and air easily move to the fabric tape 8a side.

  In the second winding step, the rubber tape 10a is wound around the fabric covering body 12a while being given a tension F2a. Due to the tension F2a, wrinkles may occur on the fabric tape 8a around which the rubber tape 10a is wound. The coating agent 16a can suppress the generation of wrinkles. The coating agent 16a can reduce the frictional resistance between the fabric tape 8a and the rubber tape 10a in the second winding step. Due to the decrease in the frictional resistance, wrinkles in the fabric tape 8a can be suppressed. Further, the coating agent 16a imparts releasability to the rubber tape 10a. Due to this releasability, the rubber tape 10a can be easily removed.

  As described above, the fabric tape 8a is wound while the tension F1a is applied, and the rubber tape 10a is wound while the tension F2a is applied. Here, the tensile stress T1a applied to the fabric tape 8a in the first winding step and the tensile stress T2a applied to the rubber tape 10a in the second winding step are defined. The tensile stress T1a is a value obtained by dividing the tension F1a by the cross-sectional area S1a of the fabric tape 8a. That is, [T1a = F1a / S1a]. This cross-sectional area S1a is measured in the fabric tape 8a in a state where tension is not applied (free). This tensile stress T1a means a tensile stress acting on the fabric tape 8a immediately before being wound. This tensile stress T1a does not mean the tensile stress acting on the fabric tape 8a in the wound state. The tensile stress T2a is a value obtained by dividing the tension F2a by the cross-sectional area S2a of the rubber tape 10a. That is, [T2a = F2a / S2a]. This cross-sectional area S2a is measured in the rubber tape 10a in a state where tension is not applied (free). The tensile stress T2a means a tensile stress that acts on the rubber tape 10a immediately before being wound. This tensile stress T2a does not mean a tensile stress that acts on the rubber tape 10a in a wound state.

  From the viewpoint of increasing the amount of resin transferred to the fabric tape 8a and suppressing the sagging of the fabric tape 8a, the tensile stress T1a is preferably 5 Mpa or more, more preferably 10 Mpa or more, more preferably 20 Mpa or more, and more preferably 25 Mpa or more. Preferably, 30 Mpa or more is more preferable. From the viewpoint of suppressing the level difference generated on the surface of the tubular body and suppressing the amount of polishing for smoothing the surface of the tubular body, the tensile stress T1a is preferably 150 Mpa or less, more preferably 100 Mpa or less, and further preferably 60 Mpa or less.

  From the viewpoint of increasing the amount of resin transferred to the fabric tape 8a, the tensile stress T2a is preferably 2 Mpa or more, more preferably 4 Mpa or more, and further preferably 6 Mpa or more. From the viewpoint of suppressing the rubber tape 10a from being cut, the tensile stress T2a is preferably 60 Mpa or less, more preferably 40 Mpa or less, more preferably 30 Mpa or less, and still more preferably 20 Mpa or less.

  From the viewpoint of increasing the amount of the resin transferred to the fabric tape 8a, the ratio (T2a / T1a) is preferably increased. When the resin moves to the woven tape, the outer diameter of the intermediate molded body is reduced. By reducing the outer diameter, the tightening force by the fabric tape 8a can be reduced. However, by winding the elastic rubber tape 10a from the outside, the tightening force to the intermediate molded body can be effectively maintained even when the outer diameter is reduced. Due to the tightening force of the rubber tape 10a, the resin easily moves to the fabric tape 8a. Further, voids in the FRP tubular body can be reduced by the tightening force of the rubber tape 10a.

  The greater the ratio (T2a / T1a), the greater the amount of resin transferred to the fabric tape 8a. In this respect, the ratio (T2a / T1a) is preferably equal to or greater than 0.1 and more preferably equal to or greater than 0.2. When the ratio (T2a / T1a) is excessively large, wrinkles or rubber tape is easily damaged. In this respect, the ratio (T2a / T1a) is preferably equal to or less than 2.0 and more preferably equal to or less than 1.8.

  In addition, when placing importance on increasing the resin transferred to the fabric tape 8a, it is preferable that the ratio (T2a / T1a) is set to be large, and specifically, the ratio (T2a / T1a) is from 1.0. The upper limit of the ratio (T2a / T1a) is preferably 2 or more from the viewpoint of suppressing the occurrence of soot. 0.0 or less is preferable, and 1.8 or less is more preferable.

  In the case where importance is placed on suppressing the generation of wrinkles, the ratio (T2a / T1a) is preferably set to be small, and specifically, the ratio (T2a / T1a) is preferably less than 1.0, and 0 .95 or less is more preferable, and 0.8 or less is more preferable. In this case, the ratio (T2a / T1a) is preferably 0.1 or more in order to secure a predetermined amount of resin to be transferred to the fabric tape 8a. .2 or more is more preferable.

  In the second winding step, when a resin film tape is used instead of the rubber tape, the tensile stress T2 of the resin film tape is preferably larger than the tensile stress T1 of the fabric tape. That is, T2> T1 is preferable. Resin film tapes are less elastic than rubber tapes, and tensile stress tends to decrease when the temperature is raised to the shaft molding temperature. This decrease in tensile stress causes a decrease in pressing force (pressure toward the inside of the shaft) by the resin film tape. Therefore, in the case of a resin film tape, it is preferable to suppress a decrease in tensile stress at the shaft molding temperature by setting T2> T1. On the other hand, due to the elasticity of rubber tape, the pressure on the shaft hardly decreases even when the temperature is raised to the shaft molding temperature. Therefore, in the case of the rubber tape, in order to effectively suppress defects such as wrinkles, it is preferable that T2a <T1a. However, as described above, if T2a> T1a, the amount of resin transferred to the fabric tape can be increased.

  Also in the second embodiment, the fiber content Z1, the fiber content Z2, and the difference (Z2-Z1) are the same as those in the first embodiment. A preferable range of the fiber content R1 in the fiber reinforced resin member is the same as that in the first embodiment. A preferable range of the content rate Rx is the same as that in the first embodiment.

  The base material 14a of the rubber tape 10a is preferably formed by vulcanization molding of a rubber composition. Examples of the base rubber of the rubber composition include natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), styrene-butadiene rubber (SBR), chloroprene rubber (CR), acrylonitrile-butadiene rubber (NBR). ), Carboxylated nitrile rubber, butyl rubber (IIR), halogenated butyl rubber (X-IIR), ethylene-propylene rubber (EPM), ethylene-propylene-diene rubber (EPDM), ethylene-vinyl acetate rubber (EVA), acrylic rubber (ACM) , ANM), ethylene-acrylic rubber, chlorosulfonated polyethylene (CSM), chlorinated polyethylene (CM), epichlorohydrin rubber (CO), urethane rubber, silicone rubber and fluorine rubber. Is mentioned. 100% by mass of base rubber is ethylene-propylene-diene rubber (EPDM), butyl rubber (IIR) or fluoro rubber because it has excellent overall performance considering heat resistance, durability, tensile strength and releasability. On the other hand, a base rubber containing 50 parts by mass or more is preferable. The rubber composition preferably contains a vulcanizing agent and is preferably sulfur crosslinked. The rubber composition may contain a vulcanization accelerator, a crosslinking initiator, a filler, a plasticizer, an antiaging agent, and the like as necessary. Examples of the vulcanization accelerator include one or more selected from a thiazole vulcanization accelerator, a thiuram vulcanization accelerator, a guanidine vulcanization accelerator, and a sulfenamide vulcanization accelerator. . Examples of the plasticizer include one or more selected from dioctyl phthalate, dibutyl phthalate, dioctyl separate, dioctyl adipate and tricresyl phosphate. Examples of the filler include carbon black and silica, and these may be used in combination.

  The thickness d2a of the rubber tape 10a is not limited. The thickness d2a of the rubber tape 10a is preferably 300 μm or more, more preferably 400 μm or more, more preferably 500 μm or more, and more preferably 550 μm or more from the viewpoint of suppressing the cutting by the tension F2a and suppressing the twist of the rubber tape itself. Is more preferable. The thickness d2a of the rubber tape 10a is 2000 μm or less from the viewpoint of suppressing an excessive level difference at the boundary between the outer tape and the inner tape that occurs when a part of the width direction of the rubber tape is wound while being overlapped. Preferably, it is 1800 μm or less, more preferably 1500 μm or less, and still more preferably 1200 μm or less.

  The width W2a of the rubber tape 10a is not limited. From the viewpoint of suppressing cutting by the tension F2a, the width W2a is preferably equal to or greater than 8 mm, more preferably equal to or greater than 10 mm, and still more preferably equal to or greater than 12 mm. From the viewpoint of suppressing wrinkles during winding, the width W2a is preferably equal to or less than 35 mm, more preferably equal to or less than 30 mm, and still more preferably equal to or less than 25 mm.

  The tape winding step preferably includes at least a step of winding the rubber tape as a wrapping tape. More preferably, the tape winding step includes a step of winding the fabric tape and a step of winding the rubber tape around the outer side of the fabric tape as in the second embodiment.

  Next, an embodiment in which only a fabric tape is used as the wrapping tape will be described with reference to FIGS. 9 to 11.

  The third embodiment is the same as the first embodiment except that the wrapping tape is only a woven tape.

  FIG. 9 is a view for explaining the manufacturing method according to the third embodiment of the present invention. Here, a golf club shaft manufacturing method will be described as an example of a tubular body manufacturing method. In this manufacturing method, first, a mandrel 2b and a fiber reinforced resin member 4b are prepared. The mandrel 2b is also called a cored bar. A typical mandrel 2b is made of a metal such as steel. The central axis of the mandrel 2b is a substantially straight line. The mandrel 2b has a circular cross-sectional shape. The mandrel 2b has a taper. Due to this taper, the mandrel 2b is made thinner toward the one end. The mandrel 2b may be partially parallel. In other words, the mandrel 2b may partially have a portion having a constant diameter. The diameter of the entire mandrel 2b may be constant.

  The mandrel 2b is the same as the mandrel 2 described above.

  In this manufacturing method, first, a step of winding a fiber reinforced resin member around a mandrel is performed.

  The prepreg 4b is the same as the prepreg 4 described above.

  Prior to the winding step, the prepreg 4b is cut into a desired shape. In the embodiment of FIG. 9, six prepregs 4b are used. In the embodiment of FIG. 9, sheets e1 to e6 are shown as examples of the cut prepreg 4b. The prepreg 4b includes so-called angle layer sheets e1, e2, straight layer sheets e3, e5, e6, and a hoop layer sheet e4. The prepreg 4b includes full length sheets e1 to e5 provided over the entire length of the shaft and a partial sheet e6 provided in a part of the shaft longitudinal direction. The specification of the prepreg 4b is not limited. The shape, thickness, fiber type, and the like of the prepreg 4b are not limited.

  In the winding process, the sheet e1 to the sheet e6 are sequentially wound around the mandrel 2b. Although not shown, prior to winding, the sheet e2 is bonded to the sheet e1. The laminated sheet group is wound around the mandrel 2b. In this bonding, the sheet e2 is turned over. By this turning over, the fibers of the sheet e1 and the fibers of the sheet e2 are oriented in opposite directions. In FIG. 9, the angles described in the sheets e1 to e6 indicate an angle θ1 formed by the shaft axis direction and the fiber orientation direction. This winding step is the same as in the first embodiment described above.

  Next, a tape winding process is performed. In this tape winding step, a wrapping tape is wound around the outer peripheral surface of the intermediate molded body 6b. 10 and 11 are partial cross-sectional perspective views showing the state of the tape winding step. 10 and 11, the intermediate molded body 6b is simply shown as a single layer. Actually, the intermediate molded body 6b includes a plurality of layers as described above.

  The wrapping tape in the tape winding process is the fabric tape 8b. In this embodiment, only a woven tape is used as the wrapping tape. In the tape winding process, only the fabric tape 8b is wound. The fabric tape 8b is a tape having a fabric as a base material. The fabric tape 8b may have a coating agent or the like on the surface of a substrate that is a fabric.

  The state of the tape winding process is shown in FIG. In the tape winding step, the fabric tape 8b is directly wound around the outer peripheral surface of the intermediate molded body 6b. The outer peripheral surface of the intermediate molded body 6b is in contact with the fabric tape 8b. The fabric tape 8b is in contact with the outer peripheral surface of the intermediate molded body 6b.

  As shown in FIG. 10, in the tape winding step, the fabric tape 8b is wound spirally. For the purpose of spirally winding, the axial direction of the intermediate molded body 6b and the longitudinal direction of the fabric tape 8b are not perpendicular to each other. The fabric tape 8b is wound around the intermediate molded body 6b without a gap. In order to eliminate the gap, the width W1b of the fabric tape 8b is wider than the winding pitch P1b. The winding pitch P1b is indicated by a double arrow in FIG. That is, the fabric tape 8b is wound in a spiral shape while a part of the width direction is overlapped. The winding pitch P1b is constant. The winding pitch P1b is constant from the tip end to the butt end of the intermediate molded body 6b. The woven tape 8b is wound by a known wrapping machine. The fabric tape 8b is wound over the entire length of the intermediate molded body 6b. As a result of the tape winding process, the entire intermediate molded body 6b is covered with the fabric tape 8b. Note that both ends (end of winding and end of winding) of the fabric tape 8b are fixed to the intermediate molded body 6b with an adhesive tape or the like. By fixing both ends, the winding of the fabric tape 8b is not naturally unwound.

  As will be described later, in the subsequent curing step, the resin contained in the intermediate molded body 6b moves to the fabric tape 8b. That is, the resin contained in the intermediate molded body 6b is absorbed into the fabric tape 8b, or passes through the fabric tape 8b and is discharged to the outside.

  From the viewpoint of increasing the amount of resin absorbed by the fabric tape 8b, the number of wrapping layers L1 of the fabric tape 8b is preferably large. The number L1 of wrapping layers is the number of layers of the fabric tape 8b wound around the intermediate molded body 6b. The number L1 of wrapping layers is determined at each point on the surface of the intermediate molded body 6b. In the spiral winding described above, if the winding pitch P1b is larger than the width W1b of the woven tape, the intermediate molded body 6b after the winding step has a portion where the number of wrapping layers L1 is zero and the number of wrapping layers L1. There is a portion where is one layer. Further, when the ratio (P1b / W1b) is more than 0.5 and less than 1.0, the intermediate molded body 6b after the winding step has a portion where the number of wrapping layers L1 is one layer and the number of wrapping layers L1. There will be a portion with two layers.

As a method for increasing the number of wrapping layers L1, the following (Method A) and (Method B) can be employed.
(Method A) The ratio (P1b / W1b) of the winding pitch P1b to the width W1b of the fabric tape is reduced.
(Method B) A plurality of windings are performed.

  Since (Method A) can increase the number of wrapping layers L1 by one winding, it can contribute to the improvement of productivity. On the other hand, (Method B) is inferior in productivity compared with (Method A) because it is necessary to repeat the winding from the tip side to the butt side and / or the winding from the tip side to the bat side. From the viewpoint of productivity, (Method A) is preferable to (Method B). However, depending on the thickness, flexibility, and the like of the fabric tape 8b, there may be a limit in reducing the ratio (P1b / W1b) and increasing the number of wrapping layers L1. In this case, (Method B) can be used effectively.

  From the viewpoint of increasing the number of wrapping layers L1 and increasing the amount of absorbed resin, the ratio (P1b / W1b) is preferably 0.70 or less, more preferably 0.50 or less, still more preferably 0.40 or less, and 0.33 The following is more preferable. In addition, when the ratio (P1b / W1b) is excessively decreased and the number of wrapping layers L1 is excessively increased, the increase in the resin absorption amount is hardly observed, but the productivity can be lowered. In this respect, the ratio (P1b / W1b) is preferably equal to or greater than 0.05, more preferably equal to or greater than 0.07, and still more preferably equal to or greater than 0.10.

  The fabric tape 8b is wound while applying a tension F1b. The intermediate formed body 6b is fastened by the fabric tape 8b by the tension F1b. By wrapping the fabric tape 8b, the fabric covering 12b is obtained. The fabric covering 12b is formed by covering the intermediate molded body 6b with a fabric tape 8b.

  FIG. 11 is a partial cross-sectional perspective view showing a second winding state when the above (Method B) is employed. In the second winding, the fabric tape 10b is directly wound around the outer peripheral surface of the fabric covering 12b. The outer peripheral surface of the fabric covering 12b and the fabric tape 10b abut. The fabric tape 10b is in contact with the outer peripheral surface of the fabric cover 12b. That is, the fabric tape 10b is in contact with the fabric tape 8b. The fabric tape 8b and the fabric tape 10b may be the same tape or different tapes.

  As shown in FIG. 11, in the second winding, the fabric tape 10b is wound spirally. This second winding can be performed in the same manner as the first winding described above. From the viewpoint of productivity, it is preferable that this second winding is not performed. From the viewpoint of increasing the difference (Z2−Z1), the second winding is preferably performed.

  The fabric tape 10b is wound while applying a tension F2b. The fabric cover 12b is fastened by the fabric tape 10b by the tension F2b. The tension F2b and the tension F1b may be the same or different.

  In addition, although the spiral pattern by the fabric tape 8b is formed in the surface of the textile covering 12b, description of the spiral pattern by this fabric tape 8b is abbreviate | omitted in FIG.

  In the embodiment of FIG. 11, the fabric tape is wound from the tip end to the butt end. In this embodiment, the winding is repeated twice. Thus, by repeating winding, the number L1 of wrapping layers can be adjusted, and the resin absorption amount can be adjusted. From the viewpoint of productivity, the number of times the fabric tape is wound in one direction (hereinafter also simply referred to as the number of windings) is preferably 3 times or less, more preferably 2 times or less, and particularly preferably 1 time. The “one direction” may be a direction from the tip side to the butt side, or a direction from the butt side to the tip side.

  After the winding process, a curing process is performed. This curing step is the same as in the first embodiment described above. As described above, this curing step preferably includes a first heating step and a second heating step.

  After the curing step, the mandrel 2b is pulled out and the fabric tape is removed to obtain a cured tubular body. Either the drawing of the mandrel 2b or the removal of the fabric tape may be performed first. From the viewpoint of workability, preferably, the fabric tape is removed after the mandrel 2b is pulled out.

  Note that a coating agent may be provided on the inner surface of the fabric tape 8b from the viewpoint of suppressing wrinkles generated on the fabric tape 8b. The inner surface of the fabric tape 8b is a surface in contact with the intermediate molded body 6b. The coating agent is preferably a fluorine compound or a silicon compound.

  In 3rd embodiment, since the fiber reinforced resin member with small fiber content rate R1 is used similarly to 1st embodiment, a shaping | molding precision improves and a void rate is suppressed. Furthermore, in 3rd embodiment, resin contained in a fiber reinforced resin member can transfer to the fabric tape 8b during a manufacturing process. The fabric tape 8b has voids and holes between the woven fibers. Therefore, the fabric tape 8b can absorb and / or transmit the resin. The fabric tape 8b makes it easy for the matrix resin to be discharged to the outside of the molded body, and the fiber content of the tubular body can be improved. Along with the matrix resin, voids can be discharged. Thereby, the weight reduction of a tubular body and the fall of a void rate can be achieved.

  In the third embodiment, the fabric tape 8b is directly wound around the outside of the intermediate molded body while applying tension. By this manufacturing method, the resin contained in the fiber reinforced resin member is absorbed by the fabric tape 8b during the heating step. By this absorption, the fiber content of the FRP tubular body can be increased without using a fiber reinforced resin member having a high fiber content. Furthermore, the fabric tape 8b can also absorb or permeate air contained in the intermediate molded body 6b. As a result, air that causes voids can easily escape and the strength of the FRP tubular body can be improved. Moreover, the textile tape 8b can give a big pressure to the intermediate molded object 6b by making the number L1 of wrapping layers into plurality. Due to this pressure, air that causes voids can be more easily removed, and the strength of the FRP tubular body can be improved. Due to this pressure, the matrix resin is more easily removed, and the weight reduction of the FRP tubular body can be achieved.

  The absorption of the resin by the fabric tape 8b is performed after winding the fiber reinforced resin member. In the present invention, an FRP tubular body having a high fiber content can be obtained without using a fiber reinforced resin member having excessively low adhesiveness. In this embodiment, the fiber reinforced resin member can be easily wound and an improvement in the fiber content can be achieved. Since the fiber content is improved during the curing process, weight reduction and a low void ratio are achieved while maintaining moldability and productivity.

  In the present embodiment, the fabric tapes are overlapped at the overlapping portion where the wrapping tapes are overlapped. In this overlapping portion, there is no resin tape layer inside the fabric tape. Therefore, resin and air can transfer to the entire woven tape including the overlapping portion, and the resin and air can easily transfer to the woven tape.

  From the viewpoint of increasing the pressure on the intermediate molded body 6b and increasing the resin absorption of the fabric tape, the average number of wrapping layers La is preferably 1 or more, more preferably 2 or more, and more preferably 3 or more. More layers are more preferred. If the average number of wrapping layers La is excessively large, an increase in the cost of the fabric tape and an increase in labor for peeling the fabric tape may occur. Further, when the average number of wrapping layers La is excessively large, wrinkles are likely to occur on the surface of the intermediate molded body 6b. From these viewpoints, the average number of wrapping layers La is preferably 15 layers or less, more preferably 12 layers or less, and still more preferably 10 layers or less.

The average number of wrapping layers La is a concept different from the number of wrapping layers L1 described above. While the number of wrapping layers L1 is determined at each point on the surface of the intermediate molded body 6b, the average number of wrapping layers La can be understood as an average value of the number of wrapping layers L1. Specifically, the average number of wrapping layers La can be determined by the following calculation formula (1).
La = St / Sn (1)
However, in the formula (1), St is the total area of the inner surface of the fabric tape in a state wound (mm ^2), the surface area of the intermediate formed body 6b at a portion Sn is in contact with the fabric tape which is wound (mm ² ). This total area St is the product of the length Nt (mm) of the wound fabric tape and the width Wa (mm) of the fabric tape. That is, St = Nt × Wa. The length Nt is measured along the longitudinal direction of the fabric tape. The length Nt is substantially equal to or longer than the length Nk of the woven tape measured in the state unwound from the intermediate molded body 6b. The case where Nt> Nk can be satisfied when the fabric tape is wound in a state of being stretched by tension. The width Wa is substantially equal to or narrower than the width W1b of the woven tape measured in a state of being unwound from the intermediate molded body 6b. The case where W1b> Wa can be satisfied is a case where the fabric tape is wound in a state where it is stretched by tension. The number of wrapping layers L1 is 0 or an integer greater than or equal to 1, but the average number of wrapping layers La may not be an integer.

  For example, when the ratio (P1b / W1b) is 0.5, W1b = Wa, and the number of windings is 1, the average number of wrapping layers La is two. In this case, if the error of the winding pitch P1b is ignored, the number of wrapping layers L1 is two in all points.

  The total area St and the surface area Sn are measured in a range from the tip end position Tp1 of the tubular body to the butt end position Bt1 of the tubular body. As described above, in the finishing process of manufacturing the tubular body, both ends of the cured tubular body may be cut. When the both ends are cut, the tip end position Tp1 of the tubular body is different from the tip end position Tp of the cured tubular body. In the case where the both end portions are not cut as described above, the tip end position Tp1 of the tubular body matches the tip end position Tp of the cured tubular body. Similarly, when both ends described above are cut, the butt end position Bt1 of the tubular body is different from the bat end position Bt of the cured tubular body. In the case where the both end portions are not cut as described above, the tip end position Tp1 of the tubular body matches the tip end position Tp of the cured tubular body. FIG. 9 shows the tip end position Tp1 and the butt end position Bt1 when both ends are cut.

  From the viewpoint of increasing the pressure on the intermediate molded body 6b and increasing the amount of resin absorbed by the fabric tape, the number of wrapping layers L1 is preferably one or more at all points from the tip end position Tp1 to the butt end position Bt1, Two or more layers are more preferable, three or more layers are more preferable, and five or more layers are still more preferable. When the number of wrapping layers L1 is excessively large, an increase in cost of the fabric tape and an increase in labor for peeling the fabric tape may occur. Further, when the number of wrapping layers L1 is excessively large, wrinkles are likely to occur on the surface of the intermediate molded body 6b. From these viewpoints, the number L1 of wrapping layers is preferably 15 layers or less, more preferably 12 layers or less, and even more preferably 10 layers or less at all points from the tip end position Tp1 to the butt end position Bt1.

  Regardless of the value of the average number of wrapping layers La, when the number of windings is one, there are portions where the number of wrapping layers L1 is one at both ends of the wound portion. For example, even when the average number of wrapping layers La is two or more, as long as the number of windings is one, the number of wrapping layers L1 is one at the start and end of winding. There is a part. The portion Xt adjacent to the winding start point and having one wrapping layer number L1 tends to have less resin transfer to the fabric tape than the other portions. Therefore, a tubular body (shaft) formed by cutting off the portion Xt is more preferable. Similarly, the portion Yt adjacent to the winding end point and having the number of wrapping layers L1 of 1 tends to have less resin transfer to the woven tape than the other portions. Therefore, a tubular body (shaft) formed by cutting off the portion Yt is more preferable. In addition, even if the number of wrapping layers L1 is one, a portion having a portion where the number of wrapping layers L1 is two or more on both sides in the axial direction does not correspond to the portion Xt. Similarly, a portion having a portion where the number of wrapping layers L1 is two or more on both sides in the axial direction does not correspond to the portion Yt even if the number of wrapping layers L1 is one. The axial direction means the axial direction of the tubular body.

  In the winding step, the woven tape 8b may be reciprocated between the tip side and the bat side for winding. For example, the fabric tape 8b may be spirally wound from the butt side toward the tip side, and then the fabric tape 8b may be spirally wound from the tip side toward the bat side. The number of windings may be increased by such reciprocal winding. In this specification, even when one round of winding is performed by such round trip winding, the number of windings is defined as two. Even when the fabric tape 8b is wound once and again without being cut halfway, the number of windings is defined as two. As described above, from the viewpoint of productivity, the method of increasing the average number of wrapping layers La is preferably a method in which the number of windings is set to 1 and the ratio (P1b / W1b) is reduced.

  As described above, the fabric tape 8b is wound while the tension F1b is applied. Here, the tensile stress T1b applied to the fabric tape 8b in the tape winding step is defined. The tensile stress T1b is a value obtained by dividing the tension F1b by the cross-sectional area Sd of the fabric tape 8b. That is, [T1b = F1b / Sd]. This cross-sectional area Sd is measured in the fabric tape 8b in a state where tension is not applied (free). This tensile stress T1b means a tensile stress acting on the fabric tape 8b immediately before being wound. This tensile stress T1b does not mean a tensile stress that acts on the fabric tape 8b in the wound state.

  From the viewpoint of increasing the amount of the resin transferred to the fabric tape 8b and suppressing the sagging of the fabric tape 8b, the tensile stress T1b is preferably 5 Mpa or more, more preferably 10 Mpa or more, more preferably 20 Mpa or more, and more preferably 25 Mpa or more. Preferably, 30 Mpa or more is more preferable. From the viewpoint of suppressing the level difference generated on the surface of the tubular body and suppressing the amount of polishing for smoothing the surface of the tubular body, the tensile stress T1b is preferably 150 Mpa or less, more preferably 100 Mpa or less, and still more preferably 60 Mpa or less.

  In addition, from the viewpoint of increasing the resin absorption, the product (La × d1) of the average number of wrapping layers La and the thickness d1 (μm) of the fabric tape 8b is preferably 100 or more, more preferably 200 or more, and 300 or more. Is more preferable, and 500 or more is more preferable. From the viewpoint of productivity, this product (La × d1) is preferably 10,000 or less, more preferably 5000 or less, more preferably 1500 or less, and still more preferably 1200 or less.

  Also in the third embodiment, the fiber content Z1, the fiber content Z2, and the difference (Z2-Z1) are the same as those in the first embodiment. A preferable range of the fiber content R1 in the fiber reinforced resin member is the same as that in the first embodiment. A preferable range of the content rate Rx is the same as that in the first embodiment.

  Hereinafter, the effects of the present invention will be clarified by examples. However, the present invention should not be construed in a limited manner based on the description of the examples.

  Examples shown in Table 1 below are examples using a fabric tape and a resin film tape. The comparative examples shown in Table 1 below correspond to the examples in Table 1.

  The examples shown in Table 2 below are examples using fabric tapes and rubber tapes. The comparative examples shown in Table 2 below correspond to the examples in Table 2.

  The examples shown in Table 3 below are examples using only fabric tape. The comparative examples shown in Table 3 below correspond to the examples in Table 3.

  First, the evaluation method will be described.

[Measurement of forward flex]
The upper side of the cured tubular body at a position 75 mm away from the butt end Bt and the lower side of the position 215 mm away from the butt end Bt were used as support points. With these two points supported, the axis direction of the cured tubular body was horizontal. Next, a weight of 2.7 kg was applied to the load point K separated by 1039 mm from the butt end Bt. The cured tubular body was bent by the weight, and the load point K was moved downward. The amount of movement of the load point K in the vertical direction is shown in the following table as a forward flex Fj.

[Wrinkle degree]
The degree of wrinkles (wrinkles) generated on the surface of the cured tubular body was evaluated by visual observation of the appearance. Evaluation was made according to the following five stages. This evaluation is shown in the table below. The smaller the evaluation score, the smaller the generation of wrinkles and the higher the evaluation.
Evaluation 1: No wrinkles.
Evaluation 2: Wrinkles are very slightly seen.
Evaluation 3: Wrinkles of an inconspicuous degree are observed.
Evaluation 4: Wrinkles are slightly noticeable.
Evaluation 5: Wrinkles are quite noticeable.

[Thickness of fabric tape]
The thickness d1 of the woven tape was measured using a digimetric micrometer according to JIS L 1096. After lapse of 10 seconds by applying a constant pressure of 240 g / cm ^2, it is measured under a pressure of 240 g / cm ² was made. Measurements were taken at five locations. The average value of the data at the five locations is shown in the following table as “thickness d1”.

[Void ratio Rb]
The void ratio Rb was calculated from the following equation by obtaining the void area Sb and the shaft cross-sectional area Sm from an image of a cross section at a point 90 mm away from the tip of the shaft.
Rb (%) = (Sb / Sm) × 100

  In the golf club shaft, since the head is attached to the tip, the strength at the tip is particularly important. The void ratio Rb has a high correlation with the shaft strength.

[Three point bending strength]
SG type three point bending strength test was adopted. This is a test established by the Product Safety Association. FIG. 12 shows a measuring method of the SG type three-point bending strength test. As shown in FIG. 12, while supporting the shaft 20 from below at the two support points e1 and e2, a load F is applied from above to below at the load point e3. The position of the load point e3 is a position that bisects the support point e1 and the support point e2. The load point e3 is a measurement point. The measurement point was a T point. The T point is a point 90 mm from the chip Tp. The value (peak value) of the load F when the shaft 20 was broken was measured. The span S was 150 mm. The measurement results are shown in the following table.

[productivity]
The evaluation was made in four stages according to the following criteria. Evaluation A has the highest productivity and is favorable. Evaluation D has the lowest productivity.
A: The heating time in the curing step is 4 hours or less.
B: The heating time in the curing step is over 4 hours and within 24 hours.
C: The heating time in the curing step is more than 24 hours and within 72 hours.
D: The heating time in the curing process exceeds 72 hours.

  Next, examples using a fabric tape and a resin film tape will be described.

[Example 1]
After applying a release agent to the mandrel shown in FIG. 1, six prepregs were wound around this mandrel to obtain an intermediate molded body. The configuration of these six prepregs was as shown in FIG. 1 and Table 5. In Table 4 below, A, B, C, D, and E are shown as prepreg part numbers. In Table 1 below, the product numbers of the prepregs used for the sheets s1 to s6 are shown by A to E in Table 4. Table 5 below shows the prepreg configuration of Example 1.

  As shown in Table 1 and Table 4, the sheet s1 and the sheet s2 are “9252S-11” manufactured by Toray Industries, Inc., the sheet s3 is “2252G-10” manufactured by Toray Industries, Inc., and the sheet s4 is manufactured by Toray Industries, Inc. “805S-3”, and sheets s5 and s6 were “2252G-10” manufactured by Toray Industries, Inc.

  The “tip ply number” in Table 5 indicates the number of windings of the prepreg at the tip end Tp. “Fiber angle θ1” in Table 5 is an orientation angle of the carbon fiber with respect to the shaft axis direction. In each prepreg, the matrix resin is an epoxy resin.

  Next, a tape winding step of winding a wrapping tape around the outer peripheral surface of the intermediate molded body was performed. The tape winding process was performed with a wrapping machine manufactured by Yokote Iron Works. As the tape winding process, a first winding process and a second winding process were performed. The first winding step was performed while applying a constant tension F1. The second winding step was performed while applying a constant tension F2. The tension F1 and the tension F2 were measured with a load cell manufactured by Nidec Sympos. Based on these tensions F1 and F2, tensile stress T1 and tensile stress T2 were calculated.

  In the first winding process, the fabric tape was wound. The product name “Nylon Taffeta” sold by Kinki Tape Co., Ltd. was used as this fabric tape. This nylon taffeta is a woven tape in which nylon fibers are woven in a plain weave. The type of nylon constituting this nylon fiber is nylon 6. The fabric tape had a width W1 of 15 mm and a thickness d1 of 100 μm. The tensile stress T1 in the first winding process was set to 35 Mpa. In the first winding step, the winding pitch P1 was 1.5 mm.

  The average number of wrapping layers La in the first winding step was 10. By setting the ratio (P1 / W1) to 0.1, the average number of wrapping layers La was set to 10.

  After the first winding step, a second winding step was performed. In the second winding step, the resin film tape was wound. A polypropylene (PP) film tape was used as this resin film tape. As this PP film tape, PT30H manufactured by Shin-Etsu Film Co., Ltd. was used. A silicon-based coating agent is provided on one surface of the film tape. The PP film tape was wound with the coating layer on the inside. The PP film tape had a width W2 of 25 mm and a thickness d2 of 30 μm. The tensile stress T2 in the second winding process was set to 85 Mpa. In the second winding step, the winding pitch P2 was 2 mm.

  A curing step was performed after the second winding step. In the curing process, a second heating step was performed after the first heating step. In the first heating step, the temperature was 80 ° C. and the time was 30 minutes. In the second heating step, the temperature was 130 ° C. and the time was 120 minutes.

  Next, the mandrel was pulled out. Next, the resin film tape and the fabric tape were removed, and a cured tubular body according to Example 1 was obtained. The specifications and evaluation results of Example 1 are shown in Table 1 below.

[Examples 2 to 5]
Except for the specifications shown in Table 1, a cured tubular body according to each example was obtained in the same manner as in Example 1. These specifications and evaluation results are shown in Table 1 below.

[Comparative Examples 1 to 4]
The second winding step was not performed, and each specification was as shown in Table 1. Others were the same as in Example 1, and cured tubular bodies of Comparative Examples 1 to 4 were obtained. These specifications and evaluation results are shown in Table 1 below.

  The PP film tapes of Comparative Example 1 and Comparative Example 2 are the same as those of Example 1. In Comparative Example 3, a PET film tape was used as the wrapping tape. As this PET film tape, the trade name “PET-25K” manufactured by Shin-Etsu Film Co., Ltd. was used. In Comparative Example 4, an integrated tape was used as the wrapping tape. This integrated tape is a tape in which a nylon taffeta having a width of 15 mm and a thickness of 100 μm and a PP film tape having a width of 15 mm and a thickness of 30 μm are integrated by heating and pressure bonding. The thickness of this integrated tape is 115 μm.

  The difference (Z2−Z1) indicates the amount of resin discharged during the curing process (decreasing amount of resin). A large difference (Z2−Z1) contributes to weight reduction. Voids can be discharged together with the resin. A large difference (Z2−Z1) also contributes to a reduction in the void ratio.

  When the amount of resin decrease is large, the outer diameter of the cured tubular body is small. When the outer diameter of the cured tubular body is small, the forward flex Fj becomes larger. Table 1 shows a value [1 / (Fj × Wt)] obtained by dividing the reciprocal (1 / Fj) of the forward flex Fj by the mass Wt of the cured tubular body. A large [1 / (Fj × Wt)] means that the rigidity per unit mass is improved. The larger [1 / (Fj × Wt)], the more lightweight.

  In Example 1, all the fiber reinforced resin members have a high resin ratio. In Example 2, the inner layer has a high resin ratio, and the outer layer has a low resin ratio. In Example 3, the layer having an absolute value of the angle θ1 of 45 degrees has a high resin ratio. The results of Examples 1 to 3 are good.

  In Example 4, all the fiber reinforced resin members have a high resin ratio. Furthermore, since the time of the 1st heating step which is low temperature is long in Example 4, the void ratio Rb is low. The result of Example 4 is good.

  In Comparative Example 1, since the wrapping tape is only the resin film tape, the difference (Z2−Z1) is small.

  In Comparative Example 2, the fiber content R1 and the fiber content Z1 are high, but the difference (Z2-Z1) is small. For this reason, the shaft is heavy and the void ratio Rb is high. In addition, the three-point bending strength is small for a large weight. That is, the three-point bending strength per unit weight is small.

  In Comparative Example 3, since the wrapping tape is only the resin film tape, the difference (Z2−Z1) is small.

  In Comparative Example 4, an integrated tape was used, but the difference (Z2−Z1) was smaller than in the example. In Comparative Example 4, the tape was kinked during lapping and wrinkles occurred.

  Next, examples using a fabric tape and a rubber tape will be described.

[Example 1a]
After applying a release agent to the mandrel shown in FIG. 5, six prepregs were wound around the mandrel to obtain an intermediate molded body. The configuration of these six prepregs was as shown in FIG. 5 and Table 6. In Table 4 below, A, B, C, D, and E are shown as prepreg part numbers. In Table 2 below, the product numbers of the prepregs used for the sheets h1 to h6 are shown by A to E in Table 4. Table 6 below shows the prepreg configuration of Example 1a.

  As shown in Table 2 and Table 4, the sheet h1 and the sheet h2 are “9252S-11” manufactured by Toray Industries, Inc., the sheet h3 is “2252G-10” manufactured by Toray Industries, Inc., and the sheet h4 is manufactured by Toray Industries, Inc. The sheet h5 and the sheet h6 are “2252G-10” manufactured by Toray Industries, Inc.

  The “tip ply number” in Table 6 indicates the number of windings of the prepreg at the tip end Tp. “Fiber angle θ1” in Table 6 is the orientation angle of the carbon fiber with respect to the shaft axis direction. In each prepreg, the matrix resin is an epoxy resin.

  Next, a tape winding step of winding a wrapping tape around the intermediate molded body was performed. The tape winding process was performed with a wrapping machine manufactured by Yokote Iron Works. As the tape winding process, a first winding process and a second winding process were performed. The first winding step was performed while applying a constant tension F1a. The second winding step was performed while applying a constant tension F2a. The tension F1a and the tension F2a were measured by a load cell manufactured by Nidec Sympos. Based on these tensions F1a and F2a, the tensile stress T1a and the tensile stress T2a were calculated.

  In the first winding process, the fabric tape was wound. The product name “Nylon Taffeta” sold by Kinki Tape Co., Ltd. was used as this fabric tape. This nylon taffeta is a woven tape in which nylon fibers are woven in a plain weave. The type of nylon constituting this nylon fiber is nylon 6. This fabric tape had a width W1a of 15 mm and a thickness d1 of 100 μm. The tensile stress T1a in the first winding step was 15 Mpa. The average number of wrapping layers La in the first winding step was 10.

  After the first winding step, a second winding step was performed. In the second winding step, a rubber tape was wound. As this rubber tape, a rubber tape in which EPDM rubber was used as a base rubber was used. This rubber tape is not provided with a coating agent. As this rubber tape, a tape obtained by cutting a product name “Neo Roofing E” manufactured by Mitsuboshi Belting Co., Ltd. so as to have the following width W2a was used. The width W2a of this rubber tape was 12.5 mm, and the thickness d2a of this rubber tape was 1000 μm. In the second winding step, the winding pitch P2a was 5 mm.

  A curing step was performed after the second winding step. In this curing process, a second heating step was performed after the first heating step. In the first heating step, the temperature was 80 ° C. and the time was 30 minutes. In the second heating step, the temperature was 130 ° C. and the time was 120 minutes.

  Next, the mandrel was pulled out. Next, the rubber tape and the fabric tape were removed to obtain a cured tubular body according to Example 1a. The specifications and evaluation results of Example 1a are shown in Table 2 below.

[Examples 2a to 5a]
Except for the specifications shown in Table 2, a cured tubular body according to each example was obtained in the same manner as Example 1a. These specifications and evaluation results are shown in Table 2 below.

[Comparative Examples 1a to 4a]
The second winding step was not performed, and each specification was as shown in Table 2. Others were the same as in Example 1a, and cured tubular bodies of Comparative Examples 1a to 4a were obtained. These specifications and evaluation results are shown in Table 2 below.

  The PP film tapes of Comparative Example 1a and Comparative Example 2a are the same as those of Example 1. In Comparative Example 3a, a PET film tape was used as the wrapping tape. As this PET film tape, the trade name “PET-25K” manufactured by Shin-Etsu Film Co., Ltd. was used. In Comparative Example 4a, an integrated tape was used as the wrapping tape. This integrated tape is a tape in which a nylon taffeta having a width of 15 mm and a thickness of 100 μm and a PP film tape having a width of 15 mm and a thickness of 30 μm are integrated by heating and pressure bonding. The thickness of this integrated tape is 115 μm.

  In Example 1a, all fiber-reinforced resin members have a high resin ratio. In Example 2a, the inner layer has a high resin ratio, and the outer layer has a low resin ratio. In Example 3a, the layer having an angle θ1 of 45 degrees in absolute value has a high resin ratio. The results of Examples 1a to 3a are good.

  In Example 4a, all the fiber reinforced resin members have a high resin ratio. Further, in Example 4a, the void ratio Rb is low because the time of the first heating step, which is a low temperature, is long. The result of Example 4a is good.

  In Comparative Example 1a, since the wrapping tape is only the resin film tape, the difference (Z2−Z1) is small.

  In Comparative Example 2a, the fiber content R1 and the fiber content Z1 are high, but the difference (Z2-Z1) is small. For this reason, the shaft is heavy and the void ratio Rb is high. In addition, the three-point bending strength is small for a large shaft weight. That is, the three-point bending strength per unit weight is small.

  In Comparative Example 3a, since the wrapping tape is only the resin film tape, the difference (Z2−Z1) is small.

  In Comparative Example 4a, an integrated tape was used, but the difference (Z2−Z1) was smaller than in the example. In Comparative Example 4a, the tape was kinked during lapping and wrinkles occurred.

  Next, an example using only a fabric tape will be described.

[Example 1b]
After applying the release agent to the mandrel shown in FIG. 9, six prepregs were wound around the mandrel to obtain an intermediate molded body. The configuration of these six prepregs was as shown in FIG. 9 and Table 7. In Table 4 below, A, B, C, D, and E are shown as prepreg part numbers. In Table 3 below, the product numbers of the prepregs used for the sheets e1 to e6 are indicated by A to E described in Table 4. Table 7 below shows the prepreg configuration of Example 1b.

  As shown in Table 3 and Table 4, the sheet e1 and the sheet e2 are “9252S-11” manufactured by Toray Industries, Inc., the sheet e3 is “2252G-10” manufactured by Toray Industries, Inc., and the sheet e4 is manufactured by Toray Industries, Inc. The sheet e5 and the sheet e6 are “2252G-10” manufactured by Toray Industries, Inc.

  The “tip ply number” in Table 7 indicates the number of windings of the prepreg at the tip end Tp. “Fiber angle θ1” in Table 7 is the orientation angle of the carbon fiber with respect to the shaft axis direction. In each prepreg, the matrix resin is an epoxy resin.

  Next, a tape winding step of winding a fabric tape around the outer peripheral surface of the intermediate molded body was performed. The tape winding process was performed with a wrapping machine manufactured by Yokote Iron Works. In the winding process, the number of windings was one. The tape winding process was performed while applying a constant tension F1b. The tension F1b was measured with a load cell manufactured by Nidec Sympos. Based on these tensions F1b, the tensile stress T1b was calculated.

  In the tape winding process, only the fabric tape was wound. The product name “Nylon Taffeta” sold by Kinki Tape Co., Ltd. was used as this fabric tape. This nylon taffeta is a woven tape in which nylon fibers are woven in a plain weave. The type of nylon constituting this nylon fiber is nylon 6. The woven tape had a width W1b of 15 mm and a thickness d1 of 100 μm. The tensile stress T1b in the tape winding process was 50 Mpa. The average number of wrapping layers La was 10.

  After the winding process, a curing process was performed. In this curing process, a second heating step was performed after the first heating step. In the first heating step, the temperature was 80 ° C. and the time was 30 minutes. In the second heating step, the temperature was 130 ° C. and the time was 120 minutes.

  Next, the mandrel was pulled out. Next, the fabric tape was removed to obtain a cured tubular body according to Example 1b. The specifications and evaluation results of Example 1b are shown in Table 3 below.

[Examples 2b to 5b]
Except for the specifications shown in Table 3, a cured tubular body according to each example was obtained in the same manner as Example 1b. These specifications and evaluation results are shown in Table 3 below.

[Comparative Examples 1b to 4b]
Other tapes were used in place of the woven tape, and the specifications were as shown in Table 3. Others were the same as in Example 1b, and cured tubular bodies of Comparative Examples 1b to 4b were obtained. These specifications and evaluation results are shown in Table 3 below.

  The PP film tapes of Comparative Example 1b and Comparative Example 2b are the same as those of Example 1. In Comparative Example 3b, a PET film tape was used as the wrapping tape. As this PET film tape, the trade name “PET-25K” manufactured by Shin-Etsu Film Co., Ltd. was used. In Comparative Example 4b, an integrated tape was used as the wrapping tape. This integrated tape is a tape in which a nylon taffeta having a width of 15 mm and a thickness of 100 μm and a PP film tape having a width of 15 mm and a thickness of 30 μm are integrated by heating and pressure bonding. The thickness of this integrated tape is 115 μm.

  In Example 1b, all the fiber reinforced resin members have a high resin ratio. In Example 2b, the inner layer has a high resin ratio, and the outer layer has a low resin ratio. In Example 3b, the layer having an angle θ1 of 45 degrees in absolute value has a high resin ratio. The results of Examples 1b to 3b are good.

  In Example 4b, all the fiber reinforced resin members have a high resin ratio. Further, in Example 4b, the void ratio Rb is low because the time of the first heating step, which is a low temperature, is long. The result of Example 4b is good.

  In Comparative Example 1b, since the wrapping tape is only the resin film tape, the difference (Z2−Z1) is small.

  In Comparative Example 2b, the fiber content R1 and the fiber content Z1 are high, but the difference (Z2-Z1) is small. For this reason, the shaft is heavy and the void ratio Rb is high. In addition, the three-point bending strength is small for a large shaft weight. That is, the three-point bending strength per unit weight is small.

  In Comparative Example 3b, since the wrapping tape is only the resin film tape, the difference (Z2−Z1) is small.

In Comparative Example 4b, an integrated tape was used, but the difference (Z2−Z1) was smaller than in the example. In Comparative Example 4b, the tape was kinked during lapping and wrinkles occurred.

  Thus, an Example is high evaluation compared with a comparative example. From this evaluation result, the superiority of the present invention is clear.

  The present invention can be applied to any FRP tubular body including a golf club shaft.

FIG. 1 is a view showing a mandrel and a prepreg that can be used in an embodiment of the present invention. FIG. 2 is a partial cross-sectional perspective view showing an example of the first winding step. FIG. 3 is a partial cross-sectional perspective view showing an example of the second winding step. FIG. 4 is a cross-sectional view of a resin film tape. FIG. 5 is a view showing a mandrel and a prepreg that can be used in another embodiment of the present invention. FIG. 6 is a partial cross-sectional perspective view showing an example of the first winding step. FIG. 7 is a partial cross-sectional perspective view showing an example of the second winding step. FIG. 8 is a cross-sectional view of a rubber tape. FIG. 9 is a view showing a mandrel and a prepreg that can be used in another embodiment of the present invention. FIG. 10 is a partial cross-sectional perspective view showing an example of a tape winding process. FIG. 11 is a partial cross-sectional perspective view showing another example of the tape winding process. FIG. 12 is a diagram showing a method for measuring the three-point bending strength.

Explanation of symbols

2 ... Mandrel 4 ... Prepreg 6 ... Intermediate molded body 8 ... Textile tape 10 ... Resin film tape 12 ... Textile covering s1, s2, s3, s4, s5, s6 -Cut prepreg sheet 2a ... mandrel 4a ... prepreg 6a ... intermediate molded body 8a ... fabric tape 10a ... rubber tape 12a ... fabric cover h1, h2, h3, h4, h5 , H6 ... cut prepreg sheet 2b ... mandrel 4b ... prepreg 6b ... intermediate molded body 8b ... woven tape 10b ... woven tape 12b ... woven covering e1, e2, e3, e4, e5, e6 ... Cut prepreg sheet 20 ... Shaft

Claims (15)

Winding a fiber reinforced resin member containing fibers and a matrix resin around a mandrel to obtain an intermediate molded body;
A tape winding step of winding a wrapping tape while applying tension to the outer peripheral surface of the intermediate molded body,
A curing step of curing the matrix resin by heating the intermediate molded body around which the wrapping tape is wound;
Drawing the mandrel after the curing step and removing the wrapping tape to obtain a cured tubular body,
Fabric tape is used as the wrapping tape,
When the fiber content of the intermediate molded body is Z1 (mass%) and the fiber content of the cured tubular body is Z2 (mass%), the difference (Z2-Z1) is 3 mass% or more and 30 mass% or less. And
A method for producing a tubular body made of a fiber reinforced resin, wherein the fiber reinforced resin member includes a fiber reinforced resin member having a fiber content R1 of 50% by mass or more and 70% by mass or less. The tape winding process
The tubular body made of fiber-reinforced resin according to claim 1, comprising a first winding step of winding a fabric tape around the outer peripheral surface of the intermediate molded body, and a second winding step of winding the resin film tape after the first winding step. Manufacturing method.   The manufacturing method according to claim 2, wherein a tensile stress T1 applied to the fabric tape in the first winding step is 5 (Mpa) or more and 150 (Mpa) or less.   When the tensile stress applied to the textile tape in the first winding step is T1, and the tensile stress applied to the resin film tape in the second winding step is T2, the ratio (T1 / T2) is The production method according to claim 2, which is 0.1 or more and 0.95 or less.   The manufacturing method according to claim 2, wherein a silicon-based or fluorine-based coating material is provided on an inner surface of the resin film tape. The curing step is
A first heating step of heating at a temperature of 70 ° C. or more and 90 ° C. or less for 120 minutes or more and 4320 minutes or less;
The manufacturing method of Claim 2 including the 2nd heating step made after the said 1st heating step and heating over the time of 10 minutes or more and 60 minutes or less at the temperature of 120 to 200 degreeC. The tape winding process
The production of a fiber-reinforced resin tubular body according to claim 1, comprising a first winding step of winding a fabric tape around the outer peripheral surface of the intermediate molded body, and a second winding step of winding the rubber tape after the first winding step. Method.   The manufacturing method according to claim 7, wherein the tensile stress T1a applied to the fabric tape in the first winding step is 5 (Mpa) or more and 150 (Mpa) or less.   When the tensile stress applied to the fabric tape in the first winding step is T1a and the tensile stress applied to the rubber tape in the second winding step is T2a, the ratio (T2a / T1a) is 0. The production method according to claim 7, which is 1 or more.   The manufacturing method according to claim 7, wherein a silicon-based or fluorine-based coating material is provided on an inner surface of the rubber tape. The curing step is
A first heating step of heating at a temperature of 70 ° C. or more and 90 ° C. or less for 120 minutes or more and 4320 minutes or less;
The manufacturing method of Claim 7 including the 2nd heating step made after the said 1st heating step and heating over the time of 10 minutes or more and 60 minutes or less at the temperature of 120 to 200 degreeC.   The method for producing a fiber-reinforced resin tubular body according to claim 1, wherein the wrapping tape is only a woven tape.   The manufacturing method according to claim 12, wherein the tensile stress T1b applied to the fabric tape in the tape winding step is 5 (Mpa) or more and 150 (Mpa) or less.   The number L1 of wrapping layers of the textile tape wound in the tape winding step is one or more layers at all points from the tip end position Tp1 of the tubular body to the butt end position Bt1 of the tubular body. Production method. The curing step is
A first heating step of heating at a temperature of 70 ° C. or more and 90 ° C. or less for 120 minutes or more and 4320 minutes or less;
The manufacturing method of Claim 12 including the 2nd heating step made after the said 1st heating step and heating over the time of 10 minutes or more and 60 minutes or less at the temperature of 120 to 200 degreeC.

Images