JP2002191734A - Golf shaft - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a golf shaft which is lightweight and has a high crushing strength and a bending strength and has a three-dimensional depth and good design. SOLUTION: Planar metal lines 4 pulled so as to be spaced apart at equal intervals d are arranged in a predetermined region on the side of a grip in a body layer 1 comprising fibers having a high strength and high elasticity and impregnated with a synthetic resin, while a light-reflecting layer 2 is provided between the layer 1 and the lines 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a golf shaft used for a golf club.

[0002]

2. Description of the Related Art In general, a golf shaft is formed by winding a filament (filament winding method) obtained by impregnating a resin into a high-strength high-elastic fiber or a prepreg (sheet winding method) formed into a sheet by aligning the filament and firing. In this case, it has both moderate bending and high rigidity. In addition, by using carbon fibers as high-strength high-elastic fibers, a golf shaft having high strength and light weight is obtained, and golf clubs using the same are widely used.

A golf shaft using carbon fibers has a bending strength or torsion of a product depending on the elastic modulus of the fibers used, the direction of the fibers to be arranged with respect to the mandrel axis, the position of the fibers with respect to the entire length or the position with respect to the radial direction. It has a significant effect on strength, crushing strength, etc. Further, since the strength characteristics of such a golf shaft have a great influence on the flight distance and directionality of a hit ball as a golf club to which a head and a grip are attached, active development of a golf shaft according to the purpose is active. It has been done. In recent years, in order to obtain characteristics that cannot be satisfied only with carbon fiber, for example, metal wires such as boron and titanium have been arranged over the entire length to improve the transmission of vibration during impact, and the wire has a small diameter and twist strength. Various materials are used in combination with carbon fiber, such as arranging a metal wire as a reinforcement at a position where the head is low.

[0004] On the other hand, recently, from the viewpoint of design, a golf shaft having a unique color sensation by expressing a metal color in addition to the strength characteristics described above has been demanded. Golf shafts with metallic coating or metal deposition are increasing. However, such decoration techniques such as metallic painting and vapor deposition can simply cause a metal color to appear on the surface, but it is difficult to express a three-dimensional appearance with depth. Also, by arranging the above-described metal wires such as titanium densely and simply revealing them on the surface of the golf shaft,
Although it is possible to develop a metal color, increase in weight is inevitable, and it is difficult to obtain ideal strength characteristics.

That is, the golf shaft is structurally
The closer to the outer layer, the greater the influence on the bending strength. However, since a metal wire having a generally circular cross section occupies a large area in the thickness direction, it is difficult to obtain ideal strength characteristics (particularly, bending strength). Also, in order to ensure visibility, metal wires are arranged near the surface having a larger diameter than the inner layer that has been conventionally arranged, so that more metal wires must be used than when they are arranged in the inner layer. In addition, since a metal wire heavier than carbon fiber is used, the weight of the golf shaft as a whole inevitably increases.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a lightweight and high crushing strength and bending strength, An object of the present invention is to provide a golf shaft excellent in design having a three-dimensional depth.

The technical measures taken by the present inventor to solve the above object are as follows: (1) In a predetermined region on the grip portion side in a body layer made of a high-strength high-elastic fiber impregnated with a synthetic resin, There is a golf shaft in which a flat metal wire aligned with an appropriate gap is arranged and a light reflecting layer is provided between the main body layer and the flat metal wire.

[0008] (2) In the golf shaft of (1), a light transmitting layer made of a porous material is provided between the light reflecting layer and the flat metal wire.

(3) In the golf shaft of (1) or (2), the light reflecting layer is a metal layer formed on the main body layer by vapor deposition.

(4) In the golf shaft according to any one of (1) to (3), the flat metal wire is covered with a protective layer made of a transparent or translucent material. Is to be.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows an embodiment of the present invention, in which a golf club C and a part of a golf shaft S used in the golf club C are enlarged. FIG. 2 is an enlarged sectional view showing a part of the golf shaft S in FIG. In this golf club C, a head H is fitted and fixed to a small-diameter end portion (head portion side) of a tapered golf shaft S, and a grip G is attached to a predetermined region from a large-diameter end portion (grip portion side). Is obtained by attaching and fixing.

In the golf shaft S used in the golf club C, the main body layer 1 is composed mainly of high-strength high-elastic fibers impregnated with a synthetic resin. As the high-strength high-elastic fiber, for example, carbon fiber or glass fiber is mainly used, and boron fiber, aramid fiber, PBO fiber, or the like is partially used. As the synthetic resin, for example, a thermosetting synthetic resin such as an epoxy resin, a phenol resin, and an unsaturated polyester can be used.For example, the resin is wound on a mandrel by a conventional method such as a filament winding method and a sheet winding method. It is formed.

The golf shaft S according to the present invention includes a light reflecting layer 2 and a flat metal wire 4 on a predetermined region of the body layer 1 on the grip mounting portion side. Light reflection layer 2
Is formed directly on the main body layer 1 or via an underlayer,
This is a layer having at least glitter and capable of reflecting light incident from the outside. This light reflection layer 2 is, for example,
By depositing a metal such as aluminum or titanium (PVD method) on the main body layer 1, it is possible to form a mirror-like metallic layer having a glittering property. Alternatively, it can also be formed by attaching a glittering seal such as a metal foil or a hologram.

The flat metal wires 4 are arranged on the light reflecting layer 2 with an appropriate gap d. This flat metal wire 4 is
For example, a linear metal having a circular cross section is formed into a flat plate shape by rolling or the like. By using a flat metal wire in this way, the thickness of the golf shaft S in the circumferential direction can be suppressed lower than when using a conventional metal wire having a circular cross section, and an increase in the weight of the entire golf shaft S is suppressed. In addition, since the visible surface area can be increased, the visibility of the metal wire can be improved, and the golf shaft S can have excellent decorativeness due to its high glitter. Titanium, aluminum, stainless steel, or the like is used as the material of the metal used for the flat metal wire 4. Titanium is desirably used in terms of weight, strength, and glitter (color).

Since the flat metal wires 4 are arranged with an appropriate gap d therebetween, the lower light reflection layer 2 can be visually recognized through the gap d between the flat metal wires 4. The decoration formed by the metal wire 4 can have depth. That is, on the appearance, the thickness 41 of the flat metal wire 4 that can be directly viewed from outside the golf shaft S and the image of the thickness of the flat metal wire 4 projected on the light reflection layer 2 can be visually recognized simultaneously. Therefore, the thickness 41 of the flat metal wire 4 and the image projected on the light reflection layer 2 allow the metal wire 4 to have a depth greater than that of the flat metal wire 4 alone, thereby giving a three-dimensional effect. In order to improve the visibility of the image projected on the light reflecting layer and the flat metal line, the flat metal line 4 is drawn with a gap d of 0.5 to 2 times the line width. It is preferable to align them.

Here, when arranging the flat metal wire 4,
Placing the flat metal wire 4 directly on the light reflection layer 2 may damage the light reflection layer 2 and affect the glitter of the light reflection layer 2. Therefore, it is preferable to form the light transmitting layer 3 made of a light transmitting material between the light reflecting layer 2 and the flat metal wire 4. As the translucent material, for example, a synthetic resin such as a transparent epoxy resin or a glass fiber prepreg impregnated with the synthetic resin can be used. The light transmitting layer 3
The thicker the thickness, the greater the depth of the finished decoration and the more three-dimensional it is. It is preferably from 10 μm to 100 μm. Further, from the viewpoint of preventing the flat metal wire 4 from being peeled or damaged, it is also possible to cover the flat metal wire 4 with a light transmitting material and form the protective layer 5 similarly to the light transmitting layer 3.

By forming the light transmitting layer 3 separating the light reflecting layer 2 and the flat metal wire 4 as described above, the light reflecting layer 2 is formed.
Not only prevents damage to the flat metal wire 4
In addition to the image having the thickness 41, the shadow of the flat metal wire 4 is projected on the light reflection layer and the image of the back surface 43 of the flat metal wire 4 is also projected, so that the decoration can have a more three-dimensional effect. You can.

By the way, the flat metal wire 4 is disposed in the vicinity of the outer circumference in the circumferential direction on the large diameter side of the golf shaft S. As described above, the closer the outer periphery of the golf shaft S is to the outer periphery, the more the bending strength and the crushing strength are affected. Therefore, it is preferable to arrange the flat metal wires 4 so as to improve the strength. That is, the bending strength and the crushing strength can be improved by arranging and arranging the flat metal wires 4 at appropriate intervals in the bias direction of 10 ° to 80 ° with respect to the axis O of the golf shaft S. it can. Further, as shown in FIG. 4, it is also possible to provide two flat metal wires 4 and to arrange the layers so that the bias directions are opposite to each other for each layer. By arranging the flat metal wires 4 in this manner, a more three-dimensional and complicated decoration can be expressed, and the golf shaft S having a balance between bending strength and crushing strength can be obtained.

Further, the light reflecting layer 2 and the flat metal wire 4 have a total length L of the golf shaft S from the viewpoint of crushing strength.
Of these, it is desirable that the golf club C be formed by attaching the head H and the grip G to the golf shaft S if the head H and the grip G are attached to the golf shaft S if the head H and the grip G are attached too much. Covers the flat metal wire 4 and its decorativeness is impaired. Conversely, if it is separated from the grip mounting portion g, the end of the flat metal wire 4 becomes apparent, which is not preferable in appearance.

Therefore, the light reflecting layer 2 and the flat metal wire 4
It is possible to arrange the flat metal wire 4 at least in an area exposed between the head H and the grip G, and to arrange a part (the end on the large diameter side) of the metal wire 4 so as to overlap the grip mounting portion g. preferable. Specifically, of the total length L of the golf shaft S, 230 mm to 280 mm from the large-diameter end.
It is desirable to dispose them in a region with a certain interval W.
As a result, the golf shaft S can have high crushing strength, and a decoration having a three-dimensional depth composed of the flat metal wire 4 and the light reflecting layer 2 can be provided by the golf club C.
Can be easily recognized near the user's hand.

Next, a specific example of a molding process of the above-described golf shaft will be described. FIG. 5 is a view showing an example of a forming process of the golf shaft S, and shows a procedure in a case where a prepreg is wound around a mandrel M by a sheet winding method. The case where the main prepreg P1 used here is mainly a carbon fiber prepreg will be described. In addition, the main prepreg P1 has a fiber direction along a prepreg (straight layer) along the axis O of the mandrel M, a prepreg (hoop layer) perpendicular to the axis O of the mandrel M, and an axis O of the mandrel M. A prepreg (bias layer) inclined with respect to the prepreg is selectively used as appropriate according to the characteristics to be obtained.

As shown in the figure, first, a tip auxiliary prepreg P2 is wound on a tapered mandrel M, and a main prepreg P1 is entirely wound thereon.
This tip auxiliary prepreg P2 and main prepreg P1
The mandrel M is wound in a predetermined area excluding the small-diameter end area A1 and the large-diameter end area A2. Here, as the main prepreg P1, the fiber direction is the axis O of the mandrel M.
In contrast, a sheet in which two bias prepregs whose fiber directions are inclined and opposite to each other are overlapped and bonded to each other, and a straight prepreg whose fiber direction is along the axis O are appropriately wound by 4 plies to 8 plies. Next, the tip auxiliary prepreg P2 is wound again for tone adjustment, and the fiber direction is appropriately selected and used according to the desired characteristics.
Thus, the main body layer 1 is formed.

Next, a metal foil P3 is wound around the main prepreg P1 at a position deviated to the large diameter side to form the light reflecting layer 2. Here, an aluminum foil is used as the foil P3. Next, an epoxy resin paint is applied or a glass fiber prepreg is wound on and around the light reflecting layer 2 to cover and solidify the light reflecting layer 2 and form the light transmitting layer 3 on the light reflecting layer 2. .

Next, a flat metal wire 4 made of titanium is wound on the light transmitting layer 2. At this time, the light transmitting layer 2 and the flat metal wire 4 may be formed in different steps, but as shown in FIG. 6, a metal wire sheet in which the flat metal wire 4 is sandwiched between two glass fiber prepregs Pg. P4 may be wound on the light reflection layer 2. By forming in this manner, the flat metal wire 4 having a high elastic modulus and difficult to wind can be easily wound, and the light transmitting layer 3 and the flat metal wire 4 for preventing the light reflecting layer 2 from being damaged can be easily wound. The protective layer 5 for preventing damage can be formed at the same time. Next, a wrapping tape t made of a heat-shrinkable resin is wound thereon, and the golf shaft S is formed by firing in a firing furnace, decentering the mandrel M, polishing the surface, painting, and the like. (Not shown)

The golf shaft S thus formed
Since the light reflecting layer 2 is formed of aluminum and the flat metal wire 4 made of titanium is disposed thereon, the light reflecting layer 2 having a silver color serves as a background of the flat metal wire 4 having a gold color. The difference in color clarifies the existence of the flat metal wire 4, gives a deep depth to the decoration composed of the light reflection layer 2 and the flat metal wire 4, and enhances the silver color of aluminum and the gold color of titanium which have brilliancy. It can give the golf shaft a sense of quality.

Here, the aluminum foil P3 and the flat metal wire 4 are wound around the main prepreg P1 at a position deviated to the large diameter side as described above. The grip G is attached to the radial end. Therefore, even if the light reflecting layer 2 and the flat metal wire 4 are formed on the grip mounting portion g, the light reflecting layer 2 and the flat metal wire 4 are hidden by the grip G, and not only the decorativeness is impaired, but also the golf shaft S The overall weight also increases. When the flat metal wire 4 is wound,
Due to the boundary between the winding end of the flat metal wire 4 and the lower light reflection layer 2 or the main body layer 1, the end of the flat metal wire 4 appears remarkably, which is not preferable in appearance. Therefore, the main prepreg P1 is wound so that the decorativeness is not impaired even when the grip g is mounted, and the ends of the light reflection layer 2 and the flat metal wire 4 are covered and hidden by the grip to be mounted later. It is preferable to wind the aluminum foil P3 and the flat metal wire 4 at an interval W of about 230 mm to 280 mm from the large diameter side end.

By the way, as described above, the golf shaft S
In the case where the flat metal wire 4 is formed, a remarkable difference in the outer diameter appears at the boundary between the portion where the flat metal wire 4 is arranged and the main body layer 1 on the smaller diameter side, a step is generated, and the flat metal wire 4 is formed. Is markedly different from the color of the lower main body layer 1 in color, which is not preferable in appearance. Therefore, as shown in FIG. 6, after winding the flat metal wire 4, the outer shape auxiliary prepreg P <b> 5 made of carbon fiber prepreg extends from the portion where the flat metal wire 4 is arranged to the main body layer 1 on the smaller diameter side. The surface may be polished after winding and firing. Thereby, the flat metal wire 4
In addition to smoothing the step formed between the metal wire and the main body layer 1, the end of the flat metal wire 4 can be covered with the carbon prepreg.

FIG. 7 shows another example of forming a golf shaft according to the present invention. The body layer 1 is formed by winding a carbon prepreg around a mandrel M, similarly to the molding example of FIG. In this example, a wrapping tape t is wound around the main body layer 1 and fired in a firing furnace to form a raw tube (main body layer 1) (FIG. 7A). The finished tube (body layer 1) is polished, putty-filled and degreased to smooth its surface (FIG. 7 (b)).

Then, the main body layer 1 having a smooth surface is placed in a vapor deposition vessel to perform metal vapor deposition (FIG. 7 (d)) to form a light reflecting layer 2. At this time, the light reflection layer 2 may be formed over the entire body layer 1, but as described above, the light reflection layer 2 may be formed only at a position biased toward the grip mounting portion g. Alternatively, a masking tape m or the like may be wound around a portion excluding the position where the light reflection layer 2 is formed (FIG. 7C), and then vapor deposition may be performed. The masking tape m is peeled off after the vapor deposition, and the portion covered by the masking tape m can be gripped by the operator in the subsequent steps, and the subsequent work can be facilitated.

Next, in order to protect the light reflecting layer 2, a clear paint such as an epoxy resin is applied and dried, and the light transmitting layer 3 is coated.
Is formed (FIG. 7E). At this time, when the light reflection layer 2 is partially formed, the light reflection layer 2 is formed not only on the light reflection layer 2 but also on the surrounding main body layer 1 so that the light reflection layer 2 can be separated. Can be prevented. The metal wire sheet P4 in which the flat metal wires 4 as shown in FIG. 8 are aligned and adhered to the glass fiber prepreg Pg is placed on the light transmitting layer 3 with the flat metal wires 4 inside (the light transmitting layer 3 side). (FIG. 7 (f)). Then, the wrapping tape is wound again, fired, polished, and the like to complete a golf shaft (not shown).

According to this molding method, by forming the light reflection layer 2 by vapor deposition, it is possible to provide a high brilliancy and to make the thickness of the light reflection layer 2 extremely thin. Thus, an increase in the weight of the golf shaft S as a whole can be suppressed.

Although the molding example of the golf shaft S according to the present invention has been described above, the present invention is not limited to the above-described molding method.

For example, it is not necessary to arrange all the flat metal wires 4 at equal intervals. For example, a predetermined pattern may be provided in the gap d where the flat metal wires 4 are to be arranged, or the circumferential direction or the axial direction is not limited to the bias direction. By using a combination of the flat metal wires 4 arranged in the same manner as described above, the degree of freedom can be given to the pattern formed by the flat metal wires 4, and the golf shaft S can also have strength according to the purpose.

In the above-described example, the example in which the main body layer 1 is formed by a sheet-like prepreg obtained by solidifying high-strength high-elasticity fibers (carbon fibers) with a synthetic resin (sheet winding method) has been described. The present invention is not limited to the above-described embodiment. For example, the main body layer 1 may be formed by a filament winding method in which a filament impregnated with a synthetic resin is wound around a mandrel M.

[0035]

As described above, according to the present invention, it is possible to obtain a golf shaft that is lightweight, has high crushing strength and bending strength, and has a three-dimensional depth and is excellent in design.

[Brief description of the drawings]

FIG. 1 is an enlarged view showing a golf club C and a part of a golf shaft S used in the golf club C. FIG.

FIG. 2 is an enlarged cross-sectional view showing a part of the golf shaft S in FIG.

FIG. 3 is another form of FIG.

FIG. 4 is another form of FIG.

FIG. 5 is a view showing an example of a molding process of a golf shaft according to the present invention.

FIG. 6 is a view showing a flat metal wire sandwiched between glass fiber prepregs used in the molding step of FIG. 5;

FIG. 7 is a view showing another example of a molding process of the golf shaft according to the present invention.

FIG. 8 is a view showing a flat metal wire attached to a glass fiber prepreg used in the forming step of FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body layer 2 Light reflection layer 3 Translucent layer 4 Flat metal wire 41 Thickness 43 Back surface 5 Protective layer A1 Small diameter side end area A2 Large diameter side end area C Golf club d Gap D Thickness g Grip mounting part G Grip H Head L Total length m Masking tape M Mandrel O Axis P1 Main prepreg P2 Tip auxiliary prepreg P3 Foil P4 Metal wire sheet P5 External auxiliary prepreg Pg Glass fiber prepreg S Golf shaft t Wrapping tape W Interval

Claims (4)

[Claims] 1. A flat metal wire, which is aligned with an appropriate gap, is disposed in a predetermined region on a grip portion side of a main body layer made of a high-strength high-elasticity fiber impregnated with a synthetic resin. A golf shaft comprising a light reflecting layer between the metal shaft and a flat metal wire. 2. The golf shaft according to claim 1, wherein a light transmitting layer made of a porous material is provided between the light reflecting layer and the flat metal wire. 3. The light reflecting layer according to claim 1, wherein the light reflecting layer is a metal layer formed on the main body layer by vapor deposition.
Or the golf shaft according to 2. 4. The golf shaft according to claim 1, wherein the flat metal wire is covered with a protective layer made of a transparent or translucent material.