JP2015016175A - Golf club shaft and golf club using the same, and method for manufacturing golf club shaft - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a golf club shaft capable of compatibly achieving high performance (vibration attenuation performance) and high endurance strength and a golf club using the same, and a method for manufacturing the golf club shaft.SOLUTION: A golf club shaft is formed by winding a prepreg, in which a reinforced fiber is impregnated with a thermosetting resin, in a plurality of layers. The golf club shaft includes: a fabric prepreg that is formed by impregnating a fabric reinforced fiber with the thermosetting resin, disposed in an innermost layer; and at least one-layer UD prepreg that is formed by impregnating reinforced fibers, the fiber directions of which are aligned in one direction, with the thermosetting resin, disposed at an outer layer of the innermost-layer fabric prepreg.

Description

  The present invention relates to a golf club shaft, a golf club using the same, and a method for manufacturing a golf club shaft.

  Instead of steel golf club shafts, FRP (Fiber Reinforced Plastics) golf club shafts, which are made by winding multiple layers of prepregs impregnated with thermosetting resin into reinforcing fibers (for example, carbon fibers) and thermosetting, are widely used. It has been. In the old days, a UD (Uni-Direction) prepreg having a fiber direction aligned in one direction as a reinforcing fiber has been used. The UD prepreg is roughly classified into a 0 ° prepreg in which the fiber direction is parallel to the shaft longitudinal direction, a bias prepreg in which the fiber direction is oblique to the shaft longitudinal direction, and a 90 ° prepreg in which the fiber direction is orthogonal to the shaft longitudinal direction. These were laminated by devising the winding (lamination) order and the number of plies (number of windings).

  With respect to a golf club shaft using only such a UD prepreg, the present applicant pays attention to using a woven prepreg using a woven reinforcing fiber as a reinforcing fiber, and the triaxial woven fabric or the four-axial woven fabric is converted into a thermosetting resin. A golf club shaft including a woven fabric prepreg impregnated in the patent is proposed and patent rights are obtained (Patent Documents 1 and 2). It has been confirmed that a golf club shaft including a woven prepreg in addition to a UD prepreg exhibits higher performance (vibration damping performance) than a conventional golf club shaft using only a UD prepreg.

  These golf club shafts are formed by winding a plurality of layers of prepregs in turn around the outer periphery of a rod-shaped mandrel (core metal). In a golf club shaft including a conventional woven prepreg including Patent Documents 1 and 2, a UD prepreg (for example, a bias prepreg or 0 ° prepreg) is first wound around a mandrel, and a woven prepreg (for example, a biaxial woven prepreg, three A shaft woven prepreg or a four-axis woven prepreg) was wound, and a UD prepreg (for example, 0 ° prepreg or 90 ° prepreg) was wound on the outermost layer. In other words, in a golf club shaft including a conventional woven prepreg, it is essential that the UD prepreg is positioned at the innermost layer and the woven prepreg is positioned at an intermediate position on the outer layer side (an intermediate position between the innermost layer and the outermost layer). The research and development was directed to the layer configuration (order, number of plies) of the prepreg on the outer peripheral side of the innermost UD prepreg.

JP 2010-75457 A Japanese Patent No. 4571212

  The inventors of the present invention have an advantage that a golf club shaft including a conventional woven prepreg including Patent Documents 1 and 2 can obtain higher performance (vibration damping performance) than a conventional golf club shaft using only a UD prepreg. On the other hand, we have found that there is room for improvement in terms of endurance strength, and have conducted extensive research.

  An object of the present invention is to obtain a golf club shaft that can achieve both high performance (vibration damping performance) and high durability, a golf club using the same, and a method for manufacturing the golf club shaft.

  The present inventors have reconsidered the conventional common sense that the UD prepreg is positioned in the innermost layer, and at the same time, if the fabric prepreg is arranged in the innermost layer and the UD prepreg is arranged on the outer layer side of the innermost fabric prepreg, The present invention has been completed with a focus on achieving both high performance (vibration damping performance) and high durability.

Although the usefulness of the present invention is shown by experimental results, the present inventors infer the reason why the durability is improved by arranging the woven fabric prepreg in the innermost layer as follows.
In the woven prepreg, since the reinforcing fibers have a woven structure, the surface of the prepreg impregnated with a thermosetting resin has unevenness on the front and back surfaces in a matrix. In the conventional structure, there is a UD prepreg in which the direction of the unevenness on the front and back sides is in a row regardless of the fiber direction on the front and back sides of the woven prepreg. For this reason, irregular irregularities exist between the woven prepreg and the UD prepregs on the front and back, and this irregularity adversely affects the durability in the state of the heat-cured golf club shaft. That is, the presence of the UD prepreg in the innermost layer means that the UD prepreg is present on the front and back sides of the woven prepreg, and this is considered to deteriorate the durability.
On the other hand, when the woven prepreg is arranged in the innermost layer, irregular irregularities formed between the prepreg to be laminated are only one side (outer peripheral surface) of the woven prepreg (the prepreg does not exist on the inner peripheral surface). ). For this reason, durability improves compared with the conventional product in which UD prepreg exists in the front and back of a textile prepreg.

  The golf club shaft of the present invention is a golf club shaft obtained by winding a plurality of layers of prepregs in which reinforcing fibers are impregnated with a thermosetting resin and thermosetting the prepregs, in which the reinforcing fibers are impregnated with a thermosetting resin. It is arranged in the innermost layer, and on the outer layer side of the woven fabric prepreg of the innermost layer, at least one UD prepreg obtained by impregnating a thermosetting resin into a reinforcing fiber having a uniform fiber direction is arranged ( Claim 1).

The number of plies of the innermost fabric prepreg is preferably 1 (Claim 2).
Here, the number of plies of the fabric prepreg of the innermost layer means that both ends in the winding direction of the fabric prepreg are abutted (complete 1 ply), and some ends in the winding direction of the fabric prepreg are slightly Including the case of overlapping by a certain amount (slightly more than a full ply) and the case of a slight amount of gap between both ends in the winding direction of the fabric prepreg (slightly less than a full ply) ( Used in approximately 1 ply).

  The thickness of the innermost fabric prepreg is preferably in the range of 0.06 mm to 0.40 mm.

Wherein it is preferred that the weight of the innermost layer of the fabric prepreg is in the range of ^{45g / m 2 ~400g / m 2} ( Claim 4).

  The innermost woven fabric prepreg includes a biaxial woven (plain woven) prepreg in which biaxial woven (plain woven) reinforced fibers are impregnated with a thermosetting resin, and a triaxial woven reinforced fiber in which three woven reinforced fibers are impregnated with a thermosetting resin. It can be composed of a shaft woven prepreg or a four-axis woven prepreg impregnated with a thermosetting resin in a four-axis woven reinforced fiber (Claim 5).

  The UD prepreg includes a pair of bias prepregs whose fiber direction is symmetric with respect to the longitudinal direction of the shaft, and a 0 ° prepreg whose fiber direction is parallel to the longitudinal direction of the shaft, in order toward the outer layer side of the innermost fabric prepreg. (Claim 6).

  The golf club of the present invention is obtained by mounting a club head and a grip on any of the above-described golf club shafts (Claim 7).

  The golf club shaft manufacturing method of the present invention is a golf club shaft manufacturing method in which a prepreg obtained by impregnating a thermosetting resin into a reinforcing fiber is wound and thermoset, and the fabric reinforcing fiber is disposed on the outer periphery of the rod-shaped mandrel. A step of winding a fabric prepreg impregnated with a thermosetting resin, and a winding of a UD prepreg impregnated with a thermosetting resin in a reinforcing fiber having a fiber direction aligned in one direction on the outer peripheral side of the fabric prepreg Thermosetting the fabric prepreg and the UD prepreg, forming a golf club shaft having the fabric prepreg disposed in the innermost layer, pulling out the rod-shaped mandrel, and the fabric prepreg being the innermost layer. And removing the placed golf club shaft (claim 8).

  It is preferable that the step of winding the fabric prepreg on the outer periphery of the rod-shaped mandrel is performed using a rolling table.

  ADVANTAGE OF THE INVENTION According to this invention, the golf club shaft which can make high performance (vibration damping performance) and high durable strength compatible, a golf club using the same, and the manufacturing method of a golf club shaft are obtained.

It is a figure which shows the prepreg laminated structure of the golf club shaft which concerns on 1st Embodiment of this invention. It is a top view which shows the structure of a triaxial fabric prepreg. It is a perspective view which shows the structure of the rolling table used in order to wind a textile fabric prepreg on the outer periphery of a rod-shaped mandrel. It is a figure which shows the prepreg laminated structure of the golf club shaft which concerns on 2nd Embodiment of this invention. It is a top view which shows the structure of a biaxial fabric prepreg. It is sectional drawing which shows the structure of a biaxial fabric prepreg. It is a figure which shows the prepreg laminated structure of the golf club shaft which concerns on 3rd Embodiment of this invention. It is a top view which shows the structure of a four axis textile prepreg. It is a figure which shows the prepreg laminated structure of the woven fabric prepreg composite golf club shaft of a conventional product. It is a conceptual diagram which shows the verification experiment for confirming the predominance of the durable strength of the shaft by this invention.

(First embodiment)
FIG. 1 shows a prepreg laminated structure of a golf club shaft 10 according to the first embodiment of the present invention. In the figure, “tip winding number” indicates the winding number (ply number) on the tip small diameter side, and “hand winding number” indicates the winding number (ply number) on the hand large diameter side. “Angle” indicates an angle of the reinforcing fiber in the prepreg with respect to the longitudinal direction of the shaft (0 ° or 45 ° in the present embodiment) and the type of the fabric prepreg (triaxial woven prepreg in the present embodiment).

  The golf club shaft 10 is formed by winding a plurality of layers of a prepreg in which a reinforcing fiber is impregnated with a thermosetting resin and thermosetting it. As the reinforcing fiber, various materials such as carbon fiber, alumina fiber, aramid fiber, glass fiber, Tyranno fiber, carbon silicate fiber, or amorphous fiber can be used. Various materials such as an epoxy resin, an unsaturated polyester resin, a phenol resin, a vinyl ester resin, or a peak resin can be used as the thermosetting resin material.

  The golf club shaft 10 is formed in a taper shape, and the outer diameter gradually increases from the tip small diameter side toward the hand large diameter side. A club head (not shown) is attached to the small diameter end of the golf club shaft 10, and a grip (not shown) is attached to the large diameter end of the golf club shaft 10.

  The golf club shaft 10 is a one-turn triaxial woven prepreg 11 in order from the inner layer side (lower layer side) to the outer layer side (upper layer side) with respect to the tapered rod-shaped mandrel (rod-shaped cored bar) 1; A pair of two-winding bias prepregs 12 and 13, a two-turn 0 ° prepreg 14, a two-turn 0 ° prepreg 15, and a triangular prepreg 16 are wound in order and thermally cured. It is. The prepregs 12 to 16 excluding the triaxial woven prepreg 11 are UD prepregs obtained by impregnating a thermosetting resin into reinforcing fibers whose fiber directions are aligned in one direction. The prepregs 11 to 15 excluding the triangular prepreg 16 are full-length layers, and are trapezoids that become narrower from the large-diameter side end toward the small-diameter side end so that the number of turns is the same when wound around the rod-shaped mandrel 1. Is formed.

  The pair of bias prepregs 12 and 13 are symmetrical with respect to the longitudinal direction of the shaft (± 45 ° in this embodiment). In the 0 ° prepregs 14 and 15 and the triangular prepreg 16, the fiber direction is parallel to the longitudinal direction of the shaft. The triangular prepreg 16 is for making the tip of the golf club shaft 10 a straight portion corresponding to the hosel diameter of a club head (not shown).

  The triaxial woven prepreg 11 arranged in the innermost layer (lowermost layer) is a sheet-like prepreg in which a triaxial woven reinforcing fiber is impregnated with a thermosetting resin.

  With reference to FIG. 2, the structure of the triaxial textile prepreg 11 is demonstrated in detail. The triaxial woven prepreg 11 is composed of a weft thread 11A perpendicular to the longitudinal direction of the golf club shaft 10 and warp threads 11B and 11C obliquely intersecting with the weft thread 11A (30 ° and −30 ° in this embodiment). The weft 11A and the warps 11B and 11C are woven alternately above and below the yarn. A hexagonal gap 11P is formed between the wefts 11A and the wefts of the warps 11B and 11C (actually, a thermosetting resin enters the gap 11P). The angle at which the weft 11A and the warps 11B and 11C are obliquely intersected is not limited.

  The golf club shaft 10 of this embodiment has succeeded in achieving both high performance (vibration damping performance) and high durability by arranging the triaxial woven prepreg 11 in the innermost layer (lowermost layer).

  “Vibration damping performance” is one of the indices indicating the ease of the golf club shaft's vibration. The higher the vibration damping performance, the harder it is to transmit the vibration impact generated at the time of hitting the golf club shaft. Even if it continues, the burden on the player's body can be reduced and the failure can be prevented.

The present inventors infer the reason why the durability is improved by arranging the fabric prepreg (in this embodiment, the triaxial fabric prepreg 11) in the innermost layer.
In the woven prepreg, since the reinforcing fibers have a woven structure, the surface of the prepreg impregnated with a thermosetting resin has unevenness on the front and back surfaces in a matrix. In the conventional structure, there is a UD prepreg in which the direction of the unevenness on the front and back sides is in a row regardless of the fiber direction on the front and back sides of the woven prepreg. For this reason, irregular irregularities exist between the woven prepreg and the UD prepregs on the front and back, and this irregularity adversely affects the durability in the state of the heat-cured golf club shaft. That is, the presence of the UD prepreg in the innermost layer means that the UD prepreg is present on the front and back sides of the woven prepreg, and this is considered to deteriorate the durability.
On the other hand, when the woven prepreg is arranged in the innermost layer, irregular irregularities formed between the prepreg to be laminated are only one side (outer peripheral surface) of the woven prepreg (the prepreg does not exist on the inner peripheral surface). ). For this reason, durability improves compared with the conventional product in which UD prepreg exists in the front and back of a textile prepreg.

By setting the number of plies of the innermost triaxial fabric prepreg 11 to 1, the triaxial fabric prepreg 11 can be directly and easily wound around the rod-shaped mandrel 1. Moreover, it can prevent that a void generate | occur | produces at the time of heat-hardening of the triaxial fabric prepreg 11. FIG.
Here, the number of plies of the triaxial woven prepreg 11 in the innermost layer means that the both ends of the winding direction of the triaxial woven prepreg 11 are abutted (completely one ply), as well as the triaxial woven prepreg 11. When the both ends of the winding direction overlap a little (a little more than one complete ply) and when there is a slight gap between the ends of the triaxial fabric prepreg 11 in the winding direction (complete It is used in a concept (substantially 1 ply) including a little less than 1 ply.
When the number of plies of the innermost triaxial fabric prepreg 11 is not 1, it is difficult to wind the triaxial fabric prepreg 11 around the rod-shaped mandrel 1. In addition, voids may occur when the triaxial woven prepreg 11 is heat-cured.

Triaxial woven fabric prepreg 11 of the innermost layer has a thickness which is set within the range of 0.06Mm～0.40Mm, its weight is set in the range of 45g / m ² ~400g / m ² . Thereby, the triaxial fabric prepreg 11 can be wound directly and easily around the rod-shaped mandrel 1, and high performance (vibration damping performance) can be obtained.
When the thickness of the innermost triaxial fabric prepreg 11 exceeds 0.40 mm and / or the weight exceeds 400 g / m ² , the triaxial fabric prepreg 11 is wound around the rod-shaped mandrel 1. Becomes difficult.
When the thickness of the innermost triaxial fabric prepreg 11 is less than 0.06 mm and / or the weight is less than 45 g / m ² , the triaxial fabric prepreg 11 is wound around the rod-shaped mandrel 1. It becomes difficult to obtain high performance (vibration damping performance).

  The golf club shaft 10 configured as described above is manufactured as follows.

First, the step of winding the triaxial woven prepreg 11 around the outer periphery of the rod-shaped mandrel 1 is executed. The number of turns (number of plies) of the triaxial woven prepreg 11 is one.
This step is performed using a rolling table 20 as shown in FIG. Thereby, the triaxial fabric prepreg 11 can be directly and easily wound around the rod-shaped mandrel 1.
More specifically, the rolling table 20 includes a lower rolling table 21, an upper rolling table 22, and a cylinder shaft 23 that moves the upper rolling table 22 up and down relative to the lower rolling table 21.
In order to wind the triaxial woven prepreg 11 around the outer periphery of the rod-shaped mandrel 1, the triaxial woven prepreg 11 is placed on the lower rolling table 21 with the lower rolling table 21 and the upper rolling table 22 separated from each other. The rod-shaped mandrel 1 is placed at the end of the triaxial woven fabric prepreg 11 which is a winding start portion, and the upper rolling table 22 is lowered onto the lower rolling table 21 by the cylinder shaft 23 to slide the mechanism (not shown). To slide the lower rolling table 21 against the upper rolling table 22. As a result, the rod-shaped mandrel 1 rolls while being pressed between the lower rolling table 21 and the upper rolling table 22, and as a result, the triaxial fabric prepreg 11 is wound around the outer periphery of the rod-shaped mandrel 1.

  Next, on the outer periphery of the triaxial woven prepreg 11, a pair of two-turn bias prepregs 12, 13, a two-turn 0 ° prepreg 14, a two-turn 0 ° prepreg 15, and a triangular prepreg 16 are provided. The steps of winding in order are executed.

  Next, the step of molding the golf club shaft 10 in which the triaxial woven fabric prepreg 11 is disposed in the innermost layer is performed by thermosetting the prepregs 11 to 16 wound around the rod-shaped mandrel 1.

  Finally, the step of pulling out the rod-shaped mandrel 1 and taking out the golf club shaft 10 in which the triaxial woven prepreg 11 is arranged in the innermost layer is executed.

(Second Embodiment)
FIG. 4 shows a prepreg laminated structure of a golf club shaft 10 ′ according to the second embodiment of the present invention.

  The golf club shaft 10 ′ of this embodiment is the same as the golf club shaft 10 (FIG. 1) of the first embodiment, but instead of the innermost layer (lowermost layer) triaxial fabric prepreg 11. A plain fabric) having a prepreg 11 '. Since other configurations are common to the golf club shaft 10 of the first embodiment, the same reference numerals are given and the description thereof is omitted.

  The innermost layer (lowermost layer) biaxial woven prepreg 11 ′ is a sheet-like prepreg obtained by impregnating a biaxial woven (plain woven) reinforcing fiber with a thermosetting resin. As shown in FIGS. 5 and 6, the biaxial woven prepreg 11 ′ has a structure in which wefts 11A ′ and warps 11B ′ orthogonal to each other are woven, and the wefts 11A ′ and the warps 11B ′ are respectively in the longitudinal direction of the shaft. Ideally, it is wound to form 45 °. Since the mandrel has a conical shape, the angle between the weft 11A ′ and the warp 11B ′ and the shaft longitudinal direction may slightly deviate from 45 ° depending on the winding mode, but the angle between the weft 11A ′ and the warp 11B ′ Since it is 90 °, it is stable. The biaxial woven prepreg 11 ′ can also be used in such a manner that one of the weft 11 A ′ and the warp 11 B ′ is parallel to the longitudinal direction of the shaft and the other is perpendicular to the longitudinal direction of the shaft.

  The golf club shaft 10 ′ of the present embodiment has a high performance (vibration damping performance) by arranging the biaxial woven prepreg 11 ′ in the innermost layer (lowermost layer), like the golf club shaft 10 of the first embodiment. And high durability strength.

The innermost biaxial woven prepreg 11 ′ has a ply number of 1, its thickness is set in the range of 0.06 mm to 0.40 mm, and its weight is 45 g / m ^{2 to} 400 g / m. It is set within the range of ² . Accordingly, the biaxial woven prepreg 11 ′ can be directly and easily wound around the rod-shaped mandrel 1. Moreover, it can prevent that a void generate | occur | produces at the time of heat-hardening of biaxial fabric prepreg 11 '.

  The golf club shaft 10 ′ configured as described above can be manufactured by the same manufacturing method as the golf club shaft 10 of the first embodiment.

(Third embodiment)
FIG. 7 shows a prepreg laminated structure of a golf club shaft 10 ″ according to the third embodiment of the present invention.

  The golf club shaft 10 ″ of the present embodiment is the triaxial of the innermost layer (lowermost layer) in the golf club shaft 10 (FIG. 1) of the first embodiment or the golf club shaft 10 ′ (FIG. 4) of the second embodiment. Instead of the fabric prepreg 11 or the biaxial fabric prepreg 11 ′, a one-turn four-axis fabric prepreg 11 ″ is provided. Since other configurations are common to the golf club shaft 10 of the first embodiment and the golf club shaft 10 ′ of the second embodiment, the same reference numerals are given and description thereof is omitted.

  The innermost layer (lowermost layer) four-axis woven prepreg 11 ″ is a sheet-like prepreg obtained by impregnating a four-axis woven reinforcing fiber with a thermosetting resin. As shown in FIG. The vertical axis thread 11A ″ parallel to the longitudinal direction of the shaft, the horizontal axis thread 11B ″ orthogonal to the vertical axis thread 11A ″, and the angle symmetric with respect to the vertical axis thread 11A ″ and the horizontal axis thread 11B ″ (for example, 45 ° And the cross-axis yarns 11C ″ and 11D ″ that are obliquely inclined at −45 °), and the vertical axis yarn 11A ″, the horizontal axis yarn 11B ″, and the oblique axis yarns 11C ″ and 11D ″ are alternately yarns. A pentagonal gap 11P ″ is formed between the vertical axis yarn 11A ″, the horizontal axis yarn 11B ″, and the oblique axis yarns 11C ″ and 11D ″ (see FIG. Actually, a thermosetting resin has entered the gap 11P ″. Note that the vertical axis thread 11A ″ ( The angle at which the horizontal axis yarn 11B ") and the oblique axis yarn 11C" (11D ") obliquely intersect is not limited.

  The golf club shaft 10 ″ of the present embodiment has the four-axis woven prepreg 11 ″ arranged in the innermost layer (lowermost layer), so that the golf club shaft 10 of the first embodiment and the golf club shaft 10 ′ of the second embodiment. Similarly, it is possible to achieve both high performance (vibration damping performance) and high durability.

The innermost layer of the four-axis woven prepreg 11 "has a ply number of 1, its thickness is set in the range of 0.06mm to 0.40mm, and its weight is 45g / m ^{2 to} 400g / m. It is set within a range of ^2. Thereby, the four-axis woven prepreg 11 "can be directly and easily wound around the rod-shaped mandrel 1. In addition, voids can be prevented from being generated during the heat curing of the four-axis woven prepreg 11 ″.

  The golf club shaft 10 '' configured as described above can be manufactured by the same manufacturing method as the golf club shaft 10 of the first embodiment and the golf club shaft 10 'of the second embodiment.

The laminated structure of the prepregs of the first to third embodiments described above is a one-turn woven prepreg (triaxial woven prepreg 11, biaxial woven prepreg 11 ′, or four-axis in order from the inner layer side to the outer layer side. A woven prepreg 11 "), a pair of two-winding bias prepregs 12 and 13, a two-turn 0 ° prepreg 14, a two-turn 0 ° prepreg 15 and a triangular prepreg 16 were wound in order. Is.
However, the laminated structure of the prepreg according to the present invention has a degree of freedom as long as the woven prepreg is arranged in the innermost layer, and various design changes are possible. For example, a 90 ° prepreg in which the fiber direction is orthogonal to the longitudinal direction of the shaft is added to the shaft intermediate layer (intermediate layer between the innermost fabric prepreg and the outermost prepreg) to strengthen against flatness. Embodiments are possible.

(Demonstration experiment for confirming superiority of durability strength of shaft according to the present invention)
The inventors actually manufactured the golf club shaft 10 of the first embodiment and the conventional woven prepreg composite golf club shaft 30 and conducted a demonstration experiment of the manufactured golf club shaft, whereby the shaft according to the present invention was obtained. The superiority of durability strength was confirmed.

  As shown in FIG. 9, the golf club shaft 30 of the conventional product is the same as the golf club shaft 10 (FIG. 1) of the first embodiment except that the innermost triaxial woven prepreg 11 is used without changing the prepreg used. It moves between the pair of bias prepregs 12 and 13 and the 0 ° prepreg 14, and the pair of bias prepregs 12 and 13 are arranged in the innermost layer.

(Endurance test data 1)
The inventors use the prepregs having the parameter characteristics (elastic modulus, thickness, resin amount, weight, product name) shown in Table 1 below, and use the golf club shaft 10 of the first embodiment and the related art. Four golf club shafts 30 (8 in total) were produced.

  As shown in FIG. 10, the present inventors orthogonally crossed the shaft longitudinal direction at a position 230 mm from the shaft tip with the eight golf club shafts produced at a position 33 mm from the shaft tip. The number of cycles (number of cycles) until the shaft was broken was measured by repeatedly applying a load in the direction. Experiments were performed with four types of load values 175N, 190N, 205N, and 220N applied to the shaft.

Table 2 shows the endurance test data 1. The golf club shaft 10 of the first embodiment is more suitable for any load value applied to the golf club shaft of 175N, 190N, 205N, and 220N. It has been proved that the number of times until the shaft breaks (number of cycles) is higher than that of the conventional golf club shaft 30 and shows high durability.

(Endurance test data 2)
The inventors of the present invention have the following parameter characteristics (elastic modulus, thickness, resin amount, weight, product name) shown in Table 3 (only the parameter characteristics of the triaxial woven prepreg 11 in relation to Table 1 of the durability test data). The golf club shafts 10 of the first embodiment and the golf club shafts 30 of the conventional product (four in total) were manufactured using each prepreg having a different number.

The present inventors conducted a durability test on the eight golf club shafts produced by the same method as when the durability test data 1 was acquired. Table 4 shows the endurance test data 2. Regardless of the load value applied to the golf club shaft of 175N, 190N, 205N, and 220N, the golf club shaft 10 of the first embodiment is more suitable. It has been proved that the number of times until the shaft breaks (number of cycles) is higher than that of the conventional golf club shaft 30 and shows high durability.

1 Bar-shaped mandrel (bar-shaped cored bar)
10 10 '10 "golf club shaft 11 triaxial woven prepreg (woven prepreg)
11A Weft 11B 11C Warp 11P Gap 11 'Biaxial fabric (plain fabric) prepreg (fabric prepreg)
11A 'weft 11B' warp 11 "four-axis woven prepreg (fabric prepreg)
11A "vertical axis thread 11B" horizontal axis thread 11C "oblique axis thread 11D" oblique axis thread 11P "gap 12 13 pair of bias prepregs 14 0 ° prepreg 15 0 ° prepreg 16 triangular prepreg 20 rolling table 21 lower rolling table 22 Upper rolling table 23 Cylinder shaft

Claims (9)

In a golf club shaft in which a plurality of layers of a prepreg impregnated with a thermosetting resin in a reinforcing fiber are wound and thermally cured,
A fabric prepreg impregnated with a thermosetting resin is placed in the innermost layer, and the outer side of the innermost fabric prepreg is impregnated with a thermosetting resin into the reinforcing fiber with the fiber direction aligned in one direction. A golf club shaft comprising at least one UD prepreg. The golf club shaft according to claim 1,
A golf club shaft in which the innermost fabric prepreg has 1 ply. The golf club shaft according to claim 1 or 2,
The golf club shaft wherein the innermost fabric prepreg has a thickness in the range of 0.06 mm to 0.40 mm. The golf club shaft according to any one of claims 1 to 3,
The golf club shaft weight of the innermost layer of the fabric prepreg is in the range of ^{45g / m 2 ~400g / m 2} . The golf club shaft according to any one of claims 1 to 4,
The innermost fabric prepreg is a biaxial woven prepreg in which a biaxial woven reinforcing fiber is impregnated with a thermosetting resin, a triaxial woven prepreg in which a triaxial woven reinforcing fiber is impregnated with a thermosetting resin, or a four-axial woven fabric reinforcement. A golf club shaft comprising a four-axis woven prepreg in which a fiber is impregnated with a thermosetting resin. The golf club shaft according to any one of claims 1 to 5,
The UD prepreg includes a pair of bias prepregs whose fiber direction is symmetric with respect to the longitudinal direction of the shaft, and a 0 ° prepreg whose fiber direction is parallel to the longitudinal direction of the shaft, in order toward the outer layer side of the innermost fabric prepreg. Including golf club shaft. A golf club comprising a golf club shaft according to claim 1 and a club head and a grip. In a golf club shaft manufacturing method in which a plurality of layers of a prepreg impregnated with a thermosetting resin in a reinforcing fiber are wound and thermally cured,
Winding a fabric prepreg impregnated with a thermosetting resin in a fabric reinforcing fiber around the outer circumference of the rod-shaped mandrel;
Winding at least one layer of a UD prepreg impregnated with a thermosetting resin in a reinforcing fiber having a fiber direction aligned in one direction on the outer peripheral side of the woven prepreg;
Thermosetting the fabric prepreg and the UD prepreg, and molding a golf club shaft having the fabric prepreg disposed in an innermost layer;
Pulling out the rod-shaped mandrel and taking out the golf club shaft in which the fabric prepreg is disposed in the innermost layer;
A method for manufacturing a golf club shaft, comprising: In the manufacturing method of the golf club shaft of Claim 8,
The step of winding the fabric prepreg on the outer periphery of the rod-shaped mandrel is a method for manufacturing a golf club shaft, which is performed using a rolling table.

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