JP2013248055A - Golf club shaft - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a golf club shaft having an improved flexural rigidity.SOLUTION: A golf club shaft (12) includes: a tubular braided fabric layer (50) containing five fiber bundle groups (X, Y, Y', Z, Z') excluding a fiber bundle group extending in parallel to a central axis A, extending with angles different to each other to the central axis A of a golf club shaft (12) and sequentially superposed; and resin impregnated to these five fiber bundle groups; and a tubular resin layer (60) arranged directly above the braided fabric layer (50) and not containing the fiber extending in parallel to the central axis A.

Description

  The present invention relates to a golf club shaft.

  As a golf club shaft according to the prior art, a golf club shaft described in JP-A-2005-238517 (Patent Document 1) is known. The golf club shaft disclosed in this document has four fiber bundle groups that extend linearly at mutually different angles with respect to the central axis of the shaft and are sequentially stacked in order to increase rigidity against twisting and crushing. And a fabric layer composed of the resin impregnated in these fiber bundle groups. These four fiber bundle groups are a fiber bundle group extending parallel and perpendicular to the central axis of the shaft, and a fiber bundle group extending at angles of +45 degrees and -45 degrees with respect to the central axis, respectively. including. Among these fiber bundle groups, the fiber bundle group extending parallel to the central axis of the shaft contributes to increasing the bending rigidity of the shaft.

JP 2005-238517 A

  However, in the golf club shaft described in Patent Document 1, among the fiber bundle groups included in the fabric layer, each fiber bundle constituting the fiber bundle group extending parallel to the central axis of the shaft is They are arranged at predetermined intervals along the direction. Therefore, in such a braided fabric layer, the bending rigidity varies due to a mixture of a portion where the fiber bundle is present and a portion where the fiber bundle is not present along the circumferential direction of the shaft.

  Accordingly, various embodiments of the present invention provide golf club shafts having improved bending stiffness.

The golf club shaft according to one aspect of the present invention extends at mutually different angles with respect to the central axis of the golf club shaft, and excludes a bundle of fiber bundles extending in parallel to the central axis, which are sequentially stacked. A tubular braid layer including at least five fiber bundle groups and a resin impregnated in the at least five fiber bundle groups; and a fiber disposed immediately above the braid layer and extending parallel to the central axis. A tubular resin layer not included.
The laminated structure according to one aspect of the present invention is a tubular laminated structure, which extends at different angles with respect to the central axis of the laminated structure and is sequentially overlapped with the central axis. A tubular braid layer including at least five fiber bundle groups excluding the fiber bundle group extending in parallel with the resin, and a resin impregnated in the at least five fiber bundle groups, and disposed immediately above the braid layer. A tubular resin layer not including fibers extending in parallel to the central axis.

  Various embodiments of the present invention can provide golf club shafts having improved bending stiffness.

FIG. 1 is a schematic view showing a configuration of a golf club provided with a golf club shaft according to an embodiment of the present invention. FIG. 2 is a schematic view showing a method for manufacturing the shaft 12 shown in FIG. FIG. 3 is an enlarged top view showing the configuration of the braid layer 50 shown in FIG. FIG. 4 is a top view showing a part of the configuration of the braided fabric layer 50 shown in FIG. 3 in a further enlarged manner. FIG. 5 is a schematic view showing a golf shaft manufacturing method according to another embodiment of the present invention. FIG. 6 is a schematic view showing a golf shaft manufacturing method according to still another embodiment of the present invention.

  Hereinafter, various embodiments will be described with reference to the drawings as appropriate. In addition, the same referential mark is attached | subjected to the common component in drawing. Further, the drawings are not necessarily shown to the same scale for convenience.

  Hereinafter, the case where the laminated structure according to various embodiments is applied to a golf club shaft that is one of industrial products will be described. The laminated structure according to these embodiments is used for a golf club shaft and tennis. The present invention is applicable to all other industrial products such as sports equipment including rackets and badminton rackets, and fishing gear including fishing rods.

  FIG. 1 is a schematic view showing a configuration of a golf club provided with a golf club shaft according to an embodiment of the present invention. As shown in FIG. 1, a golf club 10 includes a golf club shaft (hereinafter simply referred to as “shaft”) 12, a head 14 attached to one end 12 a of the shaft 12 via a hosel 14 a, and the other end of the shaft 12. And a grip 16 attached to the other end 12b so as to cover 12b.

  FIG. 2 is a schematic view showing a method for manufacturing the shaft 12 shown in FIG. As shown in FIG. 2, the shaft 12 sequentially winds (stacks) a plurality of resin layers shown from the upper side to the lower side in FIG. 2 around a rod-shaped mandrel (core metal) 20 having a central axis A. Formed). The central axis A of the mandrel 20 corresponds to the central axis of the shaft 12 that is finally formed. The one end 20a and the other end 20b of the mandrel 20 correspond to the one end 12a and the other end 12b of the shaft 12 manufactured using the mandrel 20, respectively.

The first resin layer 30 is a layer that is first wound around the mandrel 20. The first resin layer 30 is a sheet formed in a quadrilateral shape having a width that expands from one end 30a toward the other end 30b, and a plurality of reinforcing fibers arranged to extend in parallel to the central axis A. It is constituted by a prepreg sheet formed by impregnating a resin. The symbol 32 indicates that the first resin layer 30 includes a plurality of reinforcing fibers extending in parallel to the central axis A.
The first resin layer 30 is wound around the one end 20 a of the mandrel 20, thereby contributing to increasing the bending rigidity near the one end 12 a of the shaft 12 to be finally formed.

The second resin layer 40 is a layer wound around the mandrel 20 after the first resin layer 30. Similarly to the first resin layer 30, the second resin layer 40 is also a sheet formed in a quadrangular shape having a width that expands from one end 40a toward the other end 40b, and is parallel to the central axis A. It comprises a prepreg sheet formed by impregnating a resin into a plurality of reinforcing fibers arranged to extend. The symbol 42 indicates that the second resin layer 40 includes a plurality of reinforcing fibers extending parallel to the central axis A.
Similarly to the first resin layer 30, the second resin layer 40 is also wound around the one end 20a of the mandrel 20, thereby increasing the bending rigidity in the vicinity of the one end 12a of the shaft 12 to be finally formed. It contributes to making it happen.

  The braid layer 50 is a layer wound around the mandrel 20 after the second resin layer 40. The braid layer 50 is also configured by a sheet formed in a quadrangular shape having a width that expands from one end 50a toward the other end 50b. The braided fabric layer 50 extends at different angles with respect to the central axis A, and is sequentially overlapped with at least five reinforcing fiber bundle groups excluding the reinforcing fiber bundle groups extending parallel to the central axis. It is comprised by the sheet | seat formed by impregnating resin. The symbol 52 indicates that the fabric layer 50 includes five reinforcing fiber bundle groups extending in different directions. Details of the braid layer 50 will be described later in detail.

The third resin layer 60 is a layer wound around the mandrel 20 after the braided fabric layer 50. The third resin layer 60 is also composed of a sheet formed in a square shape having a width that expands from one end 60a to the other end 60b. The third resin layer 60 includes a plurality of first reinforcing fibers arranged to extend at an angle (for example, 45 degrees) with respect to the central axis A, and an angle (for example, −45) with respect to the central axis A. A prepreg sheet formed by impregnating a resin with a second plurality of reinforcing fibers that are arranged so as to extend at a degree and intersect with each other (here, orthogonal) Composed. For example, the first plurality of reinforcing fibers and the second plurality of reinforcing fibers are overlapped to form a laminated shape. The symbol 62 indicates that the third resin layer 60 includes a plurality of two types of reinforcing fibers orthogonal to each other.
The third resin layer 60 is wound over a region extending from the vicinity of one end 20a of the mandrel 20 to the vicinity of the other end 20b, thereby contributing to an increase in the torsional rigidity of the entire shaft 12 to be finally formed. Is.

The fourth resin layer 70 is a layer wound around the mandrel 20 after the third resin layer 60. The fourth resin layer 70 is a sheet formed in a trapezoidal shape having a width that expands from one end 70a to the other end 70b, and is formed of a plurality of reinforcing fibers arranged to extend parallel to the central axis A. It is constituted by a prepreg sheet formed by impregnating a resin. The symbol 72 indicates that the fourth resin layer 70 includes a plurality of reinforcing fibers extending in parallel with the central axis A.
The fourth resin layer 70 is wound over a region extending from the vicinity of one end 20a of the mandrel 20 to the vicinity of the other end 20b, thereby contributing to an increase in the bending rigidity of the entire shaft 12 that is finally formed. Is.

The fifth resin layer 80 is a layer wound around the mandrel 20 after the fourth resin layer 70. The fifth resin layer 80 is a sheet formed in a trapezoidal shape having a width that expands from one end 80a to the other end 80b, and a plurality of reinforcing fibers arranged so as to extend perpendicularly to the central axis A. It is constituted by a prepreg sheet formed by impregnating a resin. The symbol 82 indicates that the fifth resin layer 80 includes a plurality of reinforcing fibers extending perpendicularly to the central axis A.
The fifth resin layer 80 is wound over a region extending from the vicinity of one end 20a of the mandrel 20 to the vicinity of the other end 20b, thereby contributing to an increase in the crushing rigidity of the entire shaft 12 to be finally formed. Is.

The sixth resin layer 90 is a layer wound around a mandrel after the fifth resin layer 80. The sixth resin layer 90 is a sheet formed in a trapezoidal shape having a width that expands from one end 90a to the other end 90b, and is formed of a plurality of reinforcing fibers arranged so as to extend parallel to the central axis A. It is constituted by a prepreg sheet formed by impregnating a resin. The symbol 92 indicates that the sixth resin layer 90 includes a plurality of reinforcing fibers extending in parallel to the central axis A.
The sixth resin layer 90 is wound over a region extending from the vicinity of one end 20a of the mandrel 20 to the vicinity of the other end 20b, thereby contributing to an increase in the bending rigidity of the entire shaft 12 to be finally formed. Is.

The seventh resin layer 100 is a layer wound around a mandrel after the sixth resin layer 90. The seventh resin layer 100 is composed of a sheet formed in a triangular shape having a width that decreases from one end 100a toward the other end 100b. The seventh resin layer 100 includes a plurality of first reinforcing fibers arranged to extend at an angle (for example, 45 degrees) with respect to the central axis A, and an angle (for example, −45) with respect to the central axis A. A prepreg sheet formed by impregnating a resin with a second plurality of reinforcing fibers that are arranged so as to extend at a degree and intersect with each other (here, orthogonal) Composed. For example, the first plurality of reinforcing fibers and the second plurality of reinforcing fibers are overlapped to form a laminated shape. The symbol 102 indicates that the seventh resin layer 100 includes a plurality of two types of reinforcing fibers orthogonal to each other.
The seventh resin layer 100 reinforces the vicinity (tip portion) of the end 12 a of the shaft 12 that is finally formed by being wound around the end 20 a of the mandrel 20.

  In addition, the reinforced fiber used in each resin layer and the fabric layer 50 described above includes various reinforced fibers including, for example, carbon fiber, metal fiber, glass fiber, and aramid fiber. As the resin impregnated in the reinforcing fiber, either a thermosetting resin or a thermoplastic resin may be used. Available thermosetting resins include, for example, epoxy, pismaleimide, polyimide, phenol, and the like. Available thermoplastic resins include, for example, polyetheretherketone (PEEK), polyethersulfone (PES), polyetherimide (PEI), polyphenylene sulfide (PPS), polyamide (PA) and polypropylene (PP). including.

  FIG. 3 is an enlarged top view showing the configuration of the braid layer 50 shown in FIG. FIG. 4 is a top view showing a part of the configuration of the braided fabric layer 50 shown in FIG. 3 in a further enlarged manner. As shown in FIGS. 3 and 4, the fabric layers 50 are different from each other with respect to the central axis A of the mandrel 20 (the extending direction of the central axis A is the same as the “axial direction” shown in FIG. 3). 5 fiber bundles extending at an angle. Specifically, the braided fabric layer 50 extends in a first fiber bundle group X extending perpendicularly to the central axis A and at angles of + α degrees and −α degrees with respect to the central axis A, respectively. The second fiber bundle group Y and the third fiber bundle group Y ′, and the fourth fiber bundle group Z and the fifth fiber bundle extending at an angle of + β degrees and −β degrees with respect to the central axis A, respectively. And group Z ′. 3 and 4 show a configuration when α and β are 60 and 30, respectively, as an example.

  The first fiber bundle group X is composed of a plurality of fiber bundles x arranged with a distance P1 (for example, 18 mm) from each other. The second fiber bundle group Y (third fiber bundle group Y ′) is composed of a plurality of fiber bundles y (a plurality of fiber bundles y ′) that are arranged at intervals of P2 (for example, 8 mm). Is done. Similarly, the fourth fiber bundle group Z (fifth fiber bundle group Z ′) is composed of a plurality of fiber bundles z (a plurality of fiber bundles z ′) arranged at a distance P3 (for example, 9 mm) from each other. Composed. Each fiber bundle (x, y, y ', z, z') is formed, for example, by bundling hundreds to tens of thousands of fibers and then impregnating with synthetic resin.

  As is clear from FIGS. 3 and 4, the braid layer 50 does not include a fiber bundle (fiber bundle group) extending in parallel to the central axis A. If the fabric layer is configured to include a fiber bundle group extending parallel to the central axis A, and wound around the mandrel 20 and formed into a tubular shape, the fabric layer includes the shaft 12. As a result of the occurrence of a portion where the fiber bundle is present and a portion where the fiber bundle is not present, the bending rigidity varies depending on the position in the circumferential direction. However, in the present embodiment, the braid layer 50 does not include a fiber bundle (fiber bundle group) extending in parallel to the central axis A, and thus it is possible to prevent such a problem from occurring.

The braided fabric layer 50 is arranged so that the intersections of the fiber bundles x, y, y ′, z, z ′ in the five directions are minimized. In the example shown in FIG. 3, biaxial intersections N ₁ (y, y ′), N ₂ (z, z ′), N ₃ (y, z), N ₄ (y ′, z ′), N ₅ ( y, z ′), N ₆ (y ′, z) and three-axis intersections N ₇ (x, y, y ′) and N ₈ (x, z, z ′) exist. However, there are no further intersections (intersections of 4 and 5 axes). Here, since the woven fabric layer 50 in five directions is used, one intersection may be formed by a maximum of five fiber bundles x, y, y ′, z, and z ′. However, in this embodiment, biaxial intersections N ₁ , N ₂ , N ₃ , N ₄ , N ₅ , N ₆ and triaxial intersections N ₇ , N ₈ exist, but more than that, fiber bundle x, There is no intersection where y, y ′, z, and z ′ overlap. Thereby, the thickest part in the fabric layer 50 is the intersection N ₇ (x, y, y ′) and the intersection N ₈ (x, z, z ′) where the three fiber bundles are overlapped. Therefore, in the braided fabric layer 50, the occurrence of unevenness can be suppressed as much as possible, and a difference in thickness can be prevented as much as possible for each axial site or circumferential site of the braided fabric layer 50.

  It is possible to use 90 degrees, +60 degrees, −60 degrees, +30 degrees, and −30 degrees as the extending directions of the fiber bundles x, y, y ′, z, z ′, respectively, as shown in FIGS. The angle difference between adjacent fiber bundle groups in the braided fabric layer 50 can be set to 30 degrees, which is preferable in maintaining the strength balance of the shaft 12. However, for example, the angles of the fiber bundles y and y ′ with respect to the central axis A are not limited to +60 degrees and −60 degrees, respectively, and the angles of the fiber bundles z and z ′ with respect to the central axis A are each +30 degrees. It is not limited to degrees and -30 degrees.

  When the axial direction of the shaft 12 is to be reinforced, the absolute value of the angle of the fiber bundles y and y ′ with respect to the axial direction is in the range of 45 degrees to 67.5 degrees, for example, and the center of the fiber bundles z and z ′. The absolute value of the angle with respect to the axis A is preferably in the range of 0 degrees to 22.5 degrees, for example. On the other hand, when the circumferential direction of the shaft 12 is to be reinforced, the absolute value of the angle of the fiber bundle y, y ′ with respect to the central axis A is in the range of, for example, 67.5 degrees to 90 degrees, and the fiber bundles z, z It is preferable that the absolute value of the angle with respect to the axial direction of 'is in the range of 22.5 to 45 degrees, for example. Thus, by adjusting the extending direction of the fiber bundles y, y ', z, and z', the braided fabric layer 50 having various characteristics can be formed.

  The fabric layer 50 may include a resin layer (not shown) that is bonded to the upper surface or the bottom surface of the fabric layer 50 and supports the fabric layer 50. This resin layer is constituted by a prepreg sheet containing reinforcing fibers extending in an arbitrary direction, and is for maintaining the shape of the braided fabric layer 50 and facilitating handling of the braided fabric layer 50. This resin layer is further reinforced to extend in parallel to the central axis A instead of the fabric layer 50 in view of the fact that the fabric layer 50 itself does not include a fiber bundle (fiber bundle group) extending in parallel to the central axis A. Fibers can be included. Thereby, this resin layer can contribute to increasing the bending rigidity of the shaft 12 instead of the braiding layer 50. In this case, the assembled fabric layer 50 is wound around the mandrel 20 after being attached to the resin layer.

  Returning to FIG. 2, a temporary taping process is performed in a state in which the first resin layer 30, the second resin layer 40, the braided fabric layer 50, and the third resin layer 60 are sequentially wound around the mandrel 20. In this temporary taping process, first, a molding tape such as polyester is spirally wound around the outer peripheral surface of the mandrel 20 (more precisely, the third resin layer 60). By this temporary taping process, gaps generated between the resin layers and between the resin layers and the fabric layer 50 are removed as much as possible. That is, the resin layers and the fabric layers 50 extending in a tubular shape are adjusted so as to extend as much as possible in parallel (flat).

  Thereafter, the fourth resin layer 70, the fifth resin layer 80, the sixth resin layer 90, and the seventh resin layer 100 are sequentially wound around the mandrel 20. Next, a taping process is performed. This taping process is the same as the above-described temporary taping process. The mandrel around which the forming tape is wound by the taping process is accommodated in the pot and baked. Thereafter, the mandrel 20 is pulled out from the laminated structure formed on the mandrel 20, and the laminated structure becomes the shaft 12 by further cutting and polishing.

  In the present embodiment, a resin layer including reinforcing fibers extending parallel to the central axis A is not disposed “just above” the braided fabric layer 50. When such a resin layer is disposed immediately above the braided fabric layer 50, the reinforcing fibers extending in parallel to the central axis A are reinforced in the gaps present in the braided fabric layer 50, specifically, in the braided fabric layer 50. It penetrates into the space (for example, the hatched space in FIG. 4) existing between the fibers, and it becomes easy to meander. This can be a factor of reducing the bending strength (bending rigidity) of the shaft 12 to be finally formed.

  Therefore, in this embodiment, a resin layer including reinforcing fibers extending in parallel to the central axis A is not disposed immediately above the braided fabric layer 50, so that a decrease in bending rigidity of the shaft 12 can be suppressed. Specifically, for example, a resin layer including reinforcing fibers extending at an angle in the range of 10 degrees to 90 degrees (absolute value) with respect to the central axis A is disposed immediately above the fabric layer 50. The FIG. 2 shows a configuration in which a resin layer including reinforcing fibers extending at an angle of +45 degrees and −45 degrees with respect to the central axis A is disposed immediately above the fabric layer 50. . This configuration is merely an example. As shown in FIGS. 5 and 6, a resin layer containing reinforcing fibers extending perpendicularly to the central axis A (the fifth resin layer in FIG. 2) is directly above the fabric layer 50. An arbitrary resin layer including a resin layer corresponding to 80 can be disposed.

  Further, in FIG. 2, the reinforcing fibers extending in parallel to the central axis A are interposed between the fabric layer 50 and the resin layer (fourth resin layer 70) that includes the reinforcing fibers extending in parallel to the central axis A. A configuration in which one (not including) resin layer (third resin layer 60) is arranged is shown. 5 and 6 show a configuration in which two resin layers (resin layer 80 and resin layer 60) that do not include reinforcing fibers extending parallel to the central axis A are disposed. Three or more resin layers that do not contain reinforcing fibers extending in parallel to the central axis A may be arranged.

Further, in the present embodiment, as shown in FIGS. 2, 5 and 6, a resin layer (resin containing a reinforcing fiber including a reinforcing fiber extending parallel to the central axis A after the braided fabric layer 50 is disposed). A temporary taping process is performed before layer 70) is placed "first". Thus, in the stage where the resin layer containing reinforcing fibers extending parallel to the central axis A is first disposed after the assembly layer 50 is disposed, each resin layer and each resin layer are assembled. Since the gap generated between the fabric layer 50 is removed as much as possible, the reinforcing fibers extending in parallel to the central axis A are prevented from meandering, thereby further reducing the bending strength (bending rigidity) of the shaft 12. Can be suppressed.
The temporary taping process is performed after the assembly layer 50 is disposed and before the resin layer (resin layer 70) including the reinforcing fiber including the reinforcing fiber extending in parallel with the central axis A is disposed “first”. , It may be performed at any timing (for example, immediately after the braided fabric layer 50 is disposed).

  In the various embodiments described above, the description has been given by taking the example of the fabric layer including five fiber bundle groups that extend at different angles with respect to the central axis of the shaft and are sequentially stacked. The fabric layer may include six or more fiber bundle groups as long as the fiber layer does not include fiber bundle groups extending parallel to the central axis of the shaft.

12 golf club shaft A golf club shaft central axis 20 mandrel 50 braiding layer X first fiber bundle group Y second fiber bundle group Y 'third fiber bundle group Z fourth fiber bundle group Z' fifth Fiber bundle group

Claims (5)

A golf club shaft,
At least five fiber bundle groups excluding the fiber bundle groups extending at different angles with respect to the central axis of the golf club shaft and extending in parallel to the central axis, and the at least 5 A tubular braided layer comprising a resin impregnated in one fiber bundle group, and
A tubular resin layer that is disposed immediately above the fabric layer and does not include fibers extending parallel to the central axis;
A golf club shaft comprising:   2. The golf club according to claim 1, wherein the fabric layer includes fibers extending parallel to the central axis, and includes a tubular resin layer that is bonded to a lower surface of the fabric layer and supports the fabric layer. shaft.   A first fiber bundle group that extends perpendicularly to the central axis, a second fiber bundle group that extends at an angle of + α degrees and −α degrees with respect to the central axis, and a third fiber bundle layer, respectively. And a fourth fiber bundle group and a fifth fiber bundle group extending at an angle of + β degrees and −β degrees with respect to the central axis, respectively. The golf club shaft according to 2.   The tubular resin layer that is disposed on the tubular resin layer that does not include a fiber extending in parallel to the central axis and includes a fiber that extends in parallel to the central axis. The golf club shaft according to any one of the above. A tubular laminated structure,
At least five fiber bundle groups excluding fiber bundle groups extending at different angles with respect to the central axis of the laminated structure and extending in parallel to the central axis, and the at least 5 A tubular braided layer comprising a resin impregnated in one fiber bundle group, and
A tubular resin layer that is disposed immediately above the fabric layer and does not include fibers extending parallel to the central axis;
A laminated structure comprising:

Images