JP2016013229A - Shaft for golf club - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shaft for a golf club, which utilizes a characteristic of a carbon shaft and furthermore incorporates a characteristic of a steel shaft.SOLUTION: The shaft for a golf club is provided which is used for an iron club and has, as a main material, a prepreg sheet including carbon fibers. The shaft for a golf club includes: a metal fiber/metal powder layer that is composed of the prepreg sheet comprising metal fibers/metal powder having a specific gravity of 7 or more and is disposed at a limited position of 180 to 350 mm from the tip of the shaft in the vicinity of a shaft outer layer; a tip reinforcement glass layer disposed outside the metal fiber/metal powder layer and, in addition, a balance point of the shaft disposed at a position of 53% or more.

Description

  The present invention relates to a golf club shaft, and more particularly, to a golf club shaft dedicated to an iron club having characteristics as a steel shaft while having characteristics as a carbon shaft.

  The following are known as conventional techniques.

(1) Japanese Patent Application Laid-Open No. 11-206933 This publication discloses the following technique.
The static physical properties of the golf shaft, i.e., weight, bending rigidity, and torsional rigidity are not substantially affected, the timing of the dynamic play is improved, the swing is stabilized, and the shaft of the swing is stable. To make it easier to restore bending, increase the flight distance, and improve the stability of directionality, in the golf club shaft made of fiber reinforced resin, the superelastic alloy fiber is set to 0 ° ± 5 ° with respect to the shaft axis. Although it is a technique of disposing, it is a technique that does not affect the weight, rigidity and the like.

(2) Japanese Patent Laid-Open No. 2000-14844 This publication discloses the following technique.
The static physical properties of the golf shaft, i.e., weight, bending rigidity, and torsional rigidity are not substantially affected, improving the ease of timing during dynamic play, stabilizing swing and increasing flight distance. In addition, in order to make it easier to restore torsion and deflection of the shaft during swinging and to improve the stability of directionality, in the golf club shaft made of fiber reinforced resin, the superelastic alloy fiber is + ( It is a technology that is arranged at 45 ° ± 10 °) and − (45 ° ± 10 °), but it is a technology that does not affect the weight, rigidity, etc.

(3) Japanese Patent Application Laid-Open No. 2008-200116 This publication discloses the following technique.
A shaft for an iron type golf club that increases the flight distance by reducing the rigidity while increasing the weight of the shaft is disclosed. The shaft weight W converted to 39 inches is 55 to 95 g, and the average bending rigidity value EIa of the shaft is 1. Although a technique is disclosed in which the average bending rigidity value is set to be small according to the shaft weight while being set to 0.5 kgf · m ² or more, metal fiber lamination is not used.

(4) Japanese Patent No. 4955512 This publication discloses the following technique.
The static physical properties of the golf shaft, i.e., weight, bending rigidity, and torsional rigidity are not substantially affected, the timing of the dynamic play is improved, the swing is stabilized, and the shaft of the swing is stable. A fiber reinforced resin in which a plurality of prepregs impregnated with resin are wound around a reinforcing fiber sequentially and laminated, and the impregnated resin is cured in order to make it easy to restore flexure, increase flight distance, and improve directionality stability. In the golf club shaft manufactured by the present invention, at least one of the prepregs is a straight layer, the reinforcing fibers are disposed at (0 ° ± 5 °) with respect to the shaft axis, and the reinforcing fibers are superelastic alloy fibers And the carbon fiber, and the super elastic alloy fiber is a nickel / titanium alloy fiber, and {reverse flex / (forward flex + reverse flex) } A golf club shaft made of a fiber reinforced resin having a tonal rate of 50.0% or more obtained from × 100, and the prepreg having the reinforced fiber using the superelastic alloy fiber and the carbon fiber in combination is used as the shaft total length L. On the other hand, it is arranged in a range from the tip to a position of about 1/3 · L from the tip, and is a static of bending stiffness and torsional stiffness called torque expressed by the forward flex and the reverse flex. It is a technique that improves dynamic characteristics without substantially affecting physical properties, but it does not change static characteristics such as weight increase, frequency, and rigidity.

(5) Japanese Patent No. 3617797 This publication discloses the following technique.
A metal fiber or metal powder prepreg is wound around at least a part of the front end side of the full length intermediate point of the shaft so as to be mixed into the prepreg of the non-metallic fiber, and the EI value at a position of 200 mm from the front end is 3.0 to 4 .5 kgf · m ² , and its mass is 80 to 130 g, and its center of gravity is located at a distance corresponding to 45 to 51% of the total length from the tip. A shaft having the characteristics of a metal shaft preferred by advanced users, having a good flight distance and directionality, and having a good feel can be provided. However, this technique is a carbon shaft having the characteristics of a steel shaft with the center of gravity located at a position of 45 to 51% of the total length, and is not a carbon shaft that incorporates the characteristics of the steel shaft while taking advantage of the characteristics of the carbon shaft.

(6) Japanese Patent Publication No. 7-90046 This publication discloses the following technique.
The metal fibers are arranged substantially parallel to the shaft center, and the metal fibers are arranged on the outer peripheral side of the prepreg or sheet having carbon fibers, and these prepregs or sheets are completely laminated on the outer peripheral side of the metal fiber. In the sense that it is not, it is arranged in the outermost layer of the shaft. Therefore, by having these configurations, it is possible to obtain characteristics very close to the vibration characteristics of the steel shaft without any loss of characteristics of the shaft mainly composed of carbon fiber, and what characteristics the carbon shaft has. Without damaging, it can exhibit vibration characteristics very close to those of steel shafts. However, in this technique, metal fibers are arranged over the entire length of the shaft so as to bring the vibration characteristics closer to the steel shaft, and there is no description regarding weight and vibration frequency suppression.

JP-A-11-206933 JP 2000-14844 A JP 2008-200116 A Japanese Patent No. 4955512 Japanese Patent No. 3617797 Japanese Patent Publication No. 7-90046

  In the present invention, as described above, among various conventional technologies, the golf club shaft made of carbon for use in an iron club has characteristics as a steel shaft only in the vicinity of the shaft tip while taking advantage of the characteristics as a carbon shaft. It is an object of the present invention to provide a golf club shaft that has been incorporated.

  In order to achieve the above object, a golf club shaft according to claim 1 of the present invention is a golf club shaft used for an iron club, and a shaft mainly composed of a prepreg sheet having carbon fibers and having a specific gravity of 7 or more. A metal fiber / metal powder layer made of a prepreg sheet having metal fibers / metal powder is disposed in the vicinity of the shaft outer layer and limited to a position of 180 to 350 mm from the shaft tip, and the tip is outside the metal fiber / metal powder layer. A reinforcing glass layer is disposed, and further, the balance point of the shaft is disposed at a position of 53% or more.

  A golf club shaft according to a second aspect of the present invention is the golf club shaft according to the first aspect, wherein the bias comprises a prepreg sheet in which carbon fibers are arranged in the bias direction from the inner side to the outer side of the shaft. A carbon layer, a straight carbon layer made of a prepreg sheet in which carbon fibers are arranged in a straight direction, the metal fiber / metal powder layer, and the tip reinforcing glass layer are sequentially arranged.

  In addition, the golf club shaft according to claim 3 of the present invention is characterized in that in the golf club shaft according to claim 1 or 2, VOLFA (trade name) is used as the metal fiber / metal powder. .

  In the golf club shaft of the present invention having the above-described configuration, a prepreg sheet having carbon fibers is used as a main material, and the balance point (shaft center of gravity position) is arranged at a position of 53% or more like a general carbon shaft. Therefore, first, it is possible to maintain the characteristics as a carbon shaft over the entire length of the shaft, and in addition, a metal fiber / metal powder layer made of a prepreg sheet having metal fibers / metal powder having a specific gravity of 7 or more is provided. The steel shaft is limited to the position near the shaft tip because the tip reinforcing glass layer is located near the shaft outer layer and at a position 180 to 350 mm from the shaft tip and outside the metal fiber / metal powder layer. It is possible to combine these characteristics.

  Further, in the present invention, a carbon shaft having a weight of about 100 g, for example, within a shaft length suitable for an iron club and clearing the strength standard, has a specific gravity of 7 or more and a material having excellent strength and toughness. It is possible to suppress the shaft frequency by hybridizing the fiber / metal powder.

  In addition, by stacking a prepreg with metal fibers and metal powder near the tip of the shaft, it has the strength and operability of the steel shaft, and by setting the balance point to 53% or more, the ease of swinging unique to the carbon shaft is achieved. It is possible to provide a “super heavyweight iron-only carbon shaft that surpasses steel shafts that can be played by men's tour pros and top amateurs”.

  As the overall configuration of the shaft, from the inner side (inner circumference side) to the outer side (outer circumference side) of the shaft, a prepreg in which carbon fibers are arranged in the bias direction and a bias carbon layer made of carbon fibers arranged in the bias direction and carbon fibers are arranged in the straight direction. A straight carbon layer made of sheets is sequentially arranged (laminated), and first, a basic configuration as a carbon shaft is set. Then, the metal fiber / metal powder layer and the tip reinforcing glass layer are arranged (laminated) only on the outer side and in the vicinity of the tip of the shaft, thereby giving the characteristics as an iron shaft. However, even if the metal fiber / metal powder layer and the tip reinforced glass layer are arranged (laminated) only in the vicinity of the shaft tip, the balance point is arranged at 53% or more like the general carbon shaft. In the state before the metal fiber / metal powder layer and the tip reinforcing glass layer are arranged (laminated), the balance point is further arranged on the rear end side (grip side) of the shaft.

  As the metal fiber / metal powder provided in the metal fiber / metal powder layer, it is preferable to use, for example, a fiber / powder made of amorphous metal / alloy. For example, the amorphous metal fiber “Volfa” (trade name) manufactured by Unitika May be used.

  According to the present invention having the above-described configuration, the prepreg provided with the carbon fiber is the main material and the balance point is disposed at a position of 53% or more like the general carbon shaft. It is possible to maintain the characteristics as a carbon shaft, and in addition, the metal fiber / metal powder layer made of a prepreg having a metal fiber / metal powder with a specific gravity of 7 or more is in the vicinity of the outer shaft layer and is 180 to 350 mm from the shaft tip. Since the tip reinforced glass layer is arranged outside the metal fiber / metal powder layer, it is possible to combine the characteristics as a steel shaft only in the vicinity of the shaft tip. Accordingly, it is possible to provide a golf club shaft dedicated to an iron club that is easy to swing as a whole and has a hitting strength and operability at the tip of the shaft.

The front view of a golf club provided with the shaft for golf clubs concerning the example of the present invention. Explanatory drawing showing the laminated structure of the shaft Table showing examples of metal fibers provided on the shaft Table showing dimensions and weight specifications and characteristics of shafts and shafts according to comparative examples The graph which shows the rigidity distribution of the shaft which concerns on the same shaft and a comparative example

The present invention includes the following embodiments.
(1) The present invention relates to the development of a low-frequency, super-heavy shaft by a metal fiber lamination effect.
(2) The present invention provides an iron-dedicated ultra-heavy shaft having both “easiness of carbon shaft (easy to swing)” and “strength and operability of steel shaft”.
(3) In the process of manufacturing the carbon shaft for irons,
i) A prepreg sheet using a metal fiber / metal powder having a specific gravity of 7 or more (a prepreg sheet in which metal fiber or metal powder (Volfa wire, etc.) is arranged) is disposed at a position 180 to 350 mm from the shaft tip in the vicinity of the outer layer. . The metal fibers are arranged substantially parallel to the shaft axis.
ii) A tip reinforcing glass layer is disposed outside the i layer.
iii) The shaft tip diameter (head mounting portion tip diameter) is set to φ9.3 to 9.8.
(4) The position of the center of gravity (balance point) is arranged at the same position (around 55%) as the conventional carbon shaft.
(5) By using a metal fiber at the tip while maintaining the center of gravity, the steel shaft has a feeling. That is, it has the feeling of a steel shaft while maintaining the same balance point as a conventional carbon shaft.

  Next, embodiments of the present invention will be described with reference to the drawings.

  The golf club 1 shown in FIG. 1 is an iron head club, and includes a shaft 11 with an iron head 21 attached to the front end (lower end) and a grip 31 attached to the rear end (upper end). It is a laminated structure consisting of a combination of bodies. FIG. 2 shows a sheet-like state before each laminated body is wound and laminated, and one shaft 11 is manufactured by sequentially winding and laminating these sheets in a concentric shape.

  That is, as shown in FIG. 2A, first, a tip made of a prepreg sheet in which glass fibers are arranged in a straight direction (a direction parallel to or substantially parallel to the shaft axis) on the innermost side (inner peripheral side) of the shaft laminated structure. A reinforcing layer (tip-reinforced glass layer) 12 is disposed. The tip reinforcing layer 12 is disposed at a position limited to the tip of the shaft, and for this reason, the length thereof is set to be short (further shorter than the metal fiber / metal powder layer 15 described later). Further, the tip reinforcing layer 12 is formed as a right-angled triangular sheet as shown in the figure, and the right-angled corners are arranged on the shaft tip side. Therefore, the sheet end on the wide side is directed toward the front end side of the shaft, and the sheet end on the narrow side is disposed facing the rear end side of the shaft. Note that the tip reinforcing layer 12 can be omitted depending on the mandrel shape in which the prepreg sheets are laminated.

  Next, as shown in FIGS. 2B to 2E, a bias comprising a prepreg sheet in which carbon fibers are arranged in the bias direction (direction intersecting with the shaft axis) on the outer side (outer peripheral side) of the tip reinforcing layer 12. A carbon layer 13 is disposed. The bias carbon layer 13 is arranged over the entire length of the shaft, and therefore the length thereof is set to be long. As shown in the figure, a plurality (four layers in the figure) of the bias carbon layers 13 are sequentially arranged, and the bias directions of the carbon fibers are opposite in the odd-numbered bias carbon layers 13A and the even-numbered bias carbon layers 13B. , Cross each other.

  Next, as shown in FIGS. 2 (f) to 2 (h), a straight carbon layer 14 made of a prepreg sheet in which carbon fibers are arranged in a straight direction is disposed outside the bias carbon layer 13. The straight carbon layer 14 is disposed over the entire length of the shaft, and thus the length thereof is set to be long. Further, a plurality (three layers in the figure) of the straight carbon layers 14 are sequentially arranged as shown.

  Next, as shown in FIG. 2 (i), a metal fiber / metal powder layer 15 made of a prepreg sheet in which metal fibers having a specific gravity of 7 or more are arranged in the straight direction is disposed outside the straight carbon layer 14. The metal fiber / metal powder layer 15 is arranged to be limited to a position of 180 to 350 mm in actual size from the tip of the shaft. Therefore, the length thereof is set to be short. Further, the metal fiber / metal powder layer 15 is formed as a trapezoidal sheet as shown in the drawing, and the wide sheet end is directed to the shaft front end and the narrow sheet end is directed to the shaft rear end. In addition, the sheet width narrow part on the rear end side of the shaft is further cut obliquely to sharpen the tip part.

  As shown in the table of FIG. 3, as a metal fiber or metal powder having a specific gravity of 7 or more, an amorphous wire such as Volfa (trade name), super fine metal (Fe-C-Si-Mn series) (trade name), A wire with a diameter of 100 μm or less such as a piano wire or a stainless steel wire is used.

  Next, as shown in FIG. 2 (j), a tip reinforcing layer (tip reinforcing glass layer) 16 made of a prepreg sheet in which glass fibers are arranged in a straight direction outside the metal fiber / metal powder layer 15 and on the outermost side. Place. The tip reinforcing layer 16 is disposed only at the tip of the shaft, and for this reason, its length is set to be shorter (further shorter than the metal fiber / metal powder layer 15). Further, the tip reinforcing layer 16 is formed as a right-angled triangular sheet as shown in the figure, and the right-angled corners are arranged on the shaft tip side. Therefore, the sheet end on the wide side is directed toward the front end side of the shaft, and the sheet end on the narrow side is disposed facing the rear end side of the shaft.

  When the sheet of FIG. 2 (a) to (j) is wound and laminated sequentially in the same concentric form and bonded to finish the shaft 1, the dimensions / weight specifications and characteristics shown in the table of FIG. In particular, the shaft 1 according to the first and second embodiments can have a numerical value that clears the purpose in terms of weight, frequency, etc., and the rigidity distribution is also shown in the graph of FIG. It can be set as the shaft 1 which can suppress a compressive load small. In the table of FIG. 4 and the graph of FIG. 5, Example 1 is a shaft 1 having a shaft tip diameter (Tip diameter) of 9.8 mm, and Example 2 is a shaft 1 having a shaft tip diameter (Tip diameter) of 9.3 mm. The structure of both shafts 1 and the materials used are the same. Comparative Example 1 is a general carbon shaft (consisting of a carbon bias layer, a carbon straight layer, and a reinforcing layer, and does not include a metal fiber / metal powder layer), and Comparative Example 2 is a general steel shaft. Therefore, the shaft 11 has the characteristics of a carbon shaft as a whole, has the ease of swinging, and provides a golf club shaft dedicated to an iron club that exhibits the strength and operability of the steel shaft in the vicinity of the shaft tip. can do.

  The effect by having arrange | positioned the metal fiber and the metal powder layer 15 limited to the position of 180-350 mm from the shaft front-end | tip can also be demonstrated as follows.

  In other words, the effect of arranging the metal fiber / metal powder layer 15 limited to the shaft tip is not to control the shaft frequency by the straight carbon layer 14 laminated on the entire shaft, but to have excellent material properties such as strength and toughness. The purpose of this is to control the shaft frequency by laminating a metal fiber / metal powder layer 15 having a metal tip on the shaft tip, and this allows the shaft tip to incorporate the properties of steel while utilizing the properties of carbon. It can be a shaft. The above numerical value means that the metal fiber / metal powder layer 15 is laminated in a range of ¼ to ３ with respect to the entire length of the shaft. If this range is exceeded, it may be considered that the feeling other than the shaft tip is affected. . Moreover, since the shaft tip becomes heavy, the balance point may be slightly on the shaft tip side as compared with a general carbon shaft.

  Also, according to a general carbon shaft, the rigidity of the shaft tip is increased and the vibration frequency is increased, resulting in a relatively hard image feeling. However, the shaft is formed by laminating a metal fiber / metal powder layer 15 on the shaft tip. It is possible to realize a feeling that suppresses the rigidity of the tip and does not lose.

DESCRIPTION OF SYMBOLS 1 Golf club 11 Shaft 12 Tip reinforcement layer 13 Bias carbon layer 14 Straight carbon layer 15 Metal fiber and metal powder layer 16 Tip reinforcement glass layer 31 Grip

Claims (3)

A shaft for a golf club used for an iron club, wherein the shaft mainly includes a prepreg sheet having carbon fibers.
A metal fiber / metal powder layer made of a prepreg sheet having a metal fiber / metal powder with a specific gravity of 7 or more is arranged near the outer shaft layer and at a position 180 to 350 mm from the shaft tip, and the metal fiber / metal powder layer A golf club shaft, wherein a tip reinforcing glass layer is disposed on the outer side of the shaft, and the balance point of the shaft is further disposed at a position of 53% or more. The golf club shaft according to claim 1,
A bias carbon layer made of a prepreg sheet in which carbon fibers are arranged in the bias direction from the inside to the outside of the shaft, a straight carbon layer made of a prepreg sheet in which carbon fibers are arranged in the straight direction, the metal fiber / metal powder layer, and A shaft for a golf club, wherein the tip reinforcing glass layers are sequentially arranged. The golf club shaft according to claim 1 or 2,
A golf club shaft using Volfa (trade name) as the metal fiber / metal powder.

Images