JP2002011130A - FRP bat for baseball or softball - Google Patents

Abstract

(57) [Summary] [PROBLEMS] In a FRP bat, both conflicting demands of having impact resistance and durability without cracking or cracking on the hitting ball surface and having great resilience performance are satisfied. And solve it at low cost. SOLUTION: A metal tubular member 3 is arranged on a surface layer of a hitting portion 2 of a bat in which a bat body is formed by laminating FRP5 such as glass fiber reinforced plastic or carbon fiber reinforced plastic. The WBL 4 is provided between the layers 3 and FRP5, or between the metal tubular member 3 and FRP5 and between the layers of FRP5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in an FRP bat for baseball or softball. In the baseball or softball FRP bat of the present invention, the bat body is made of glass fiber reinforced plastic (hereinafter, GFR).
It is called P. ) And carbon fiber reinforced plastics (hereinafter,
It is called CFRP. ) And other fiber-reinforced plastics (hereinafter
It is called FRP. ) A bat formed of a material and having a metal tubular member disposed on a surface layer of a hitting portion, and a weak boundary layer (hereinafter, referred to as WBL) serving as an interface peeling layer formed inside the bat. The present invention relates to a bat capable of imparting excellent rebound performance so that a ball can be hit far when hit.

[0002]

2. Description of the Related Art Conventional baseball or softball bats include wooden bats, metal bats such as titanium alloys and aluminum alloys, and yarns, fibers, and sleeves made of carbon fiber, glass fiber, or the like. Bats made of various materials, such as FRP bats formed by impregnating and curing a matrix resin typified by a synthetic resin or other matrix resins, are supplied to the market.

[0003] Even in the conventional FRP bat, in order to improve the resilience performance of the bat, the types and directions of the fibers of the FRP material such as GFRP and CFRP, the method of use, and the method of use are complicated. Those formed in combination with a metal are known.

For example, in Japanese Utility Model Laid-Open No. 4-20372, F
A bat in which a light alloy cylinder or a thermoplastic plastic cylinder made of a material different from that of the bat body is provided on the hitting portion of the RP bat in any of the outermost layer, the interlayer, and the innermost layer.

[0005] In another FRP bat, there is also an invention in which a WBL is provided between layers of the FRP material forming the bat body to achieve both resilience performance and durability.

[0006]

As the thickness of the hitting portion of the bat becomes thinner, the amount of deformation of the bat body increases, and the bat body is restored from its deformed state to its original shape by a restoring force. It is possible to fly the hit ball farther. On the other hand, if the thickness of the hitting portion is too thin, the strength of the bat body will be insufficient, and when the ball is hit, a problem such as the bat body becoming dented or cracking may occur. is there.

[0007] The FR invented in Japanese Utility Model Application Laid-Open No. 4-20372.
The P bat is durable because the FRP bat main body and the metal tubular member of the hitting portion are firmly fixed by an adhesive or the like, but the bat main body is hardly deformed, and the resilience performance is different from that of the conventional product. There was a problem that did not change.

In the case of an FRP bat in which a WBL is provided between layers of the FRP material forming the bat body, the surface of the hitting portion is made of an FRP material. There were problems with impact resistance, such as cracks and cracks on the surface.

Accordingly, the present invention provides two conflicting demands for an FRP bat, which has impact resistance and durability without cracks or cracks on the hitting ball surface and has a large rebound performance. While balancing
The purpose is to solve this problem at low cost.

[0010]

According to a first aspect of the present invention, there is provided a bat in which a bat body is formed by laminating a fiber reinforced plastic such as a glass fiber reinforced plastic or a carbon fiber reinforced plastic. A FRP bat for baseball or softball, wherein a metal tubular member is arranged, and a WBL is provided between layers of the metal tubular member and the fiber reinforced plastic.

By arranging the metal tubular member on the surface layer of the hitting portion as described above, it is possible to prevent cracks or cracks from being generated on the hitting portion surface of the FRP bat.
Also, by providing the hitting portion with the WBL, the hitting portion is easily deformed and the resilience is improved.

According to a second aspect of the present invention, in the bat according to the first aspect, the WBL is provided between layers of a fiber-reinforced plastic.
This is an RP bat.

By providing the WBLs between the layers of the FRP laminated as described above, two or more WBLs are formed, and the resilience performance is further improved.

According to a third aspect of the present invention, in the bat according to any one of the first to second aspects, the WBL is provided only at a specific portion between the layers. It is a bat made.

By providing the WBL at a specific portion between the layers as described above, the metal tubular member can be firmly fixed to the bat main body, the resilience can be increased only at the specific portion of the hitting portion where the WBL is formed, and the design can be improved. A bat according to the intention can be obtained.

According to a fourth aspect of the present invention, there is provided the bat according to any one of the first to third aspects, wherein the WBL is formed by laminating a film material. Or it is an FRP bat for softball.

According to a fifth aspect of the present invention, there is provided the bat according to any one of the first to third aspects, wherein the WBL is formed by applying a release agent. This is an FRP bat for softball.

According to the fourth aspect of the present invention, the WBL is formed by laminating a film-like material, or as in the fifth aspect, the WBL is formed by applying a release agent. Thus, it is possible to manufacture a bat according to the design intention by a simple method.

[0019]

FIG. 1 is an overall explanatory view showing an intervening portion of a WBL of an FRP bat for baseball or softball according to the present invention, and FIG. 2 is a cross-sectional view at the center of a hitting portion in FIG. It is.

As shown in FIG. 1 and FIG.
A metal tubular member is arranged on a surface layer of a hitting portion of a P bat, and a WBL is provided between the FRP and the metallic tubular member.

In order to further improve the resilience performance, WBL
It is effective to provide also between the layers of the FRP in which the layers are stacked. The WBL can be provided between a plurality of layers of the FRP, but it is desirable to form one WBL in consideration of durability.

It is desirable that the WBL be provided on the entire hitting portion. However, if the WBL is provided on the entire metallic tubular member disposed on the surface layer of the hitting portion, the metallic tubular member may rotate at the time of hitting. . In order to prevent this, it is preferable to provide the WBL only in a specific portion and fix the other portion to the FRP.

The WBL is formed by laminating a release film or by applying a release agent. Therefore, no gap is provided in the WBL. As the release film, polyethylene, polypropylene, silicon, a film such as tetrafluorocarbon,
As the release agent, a silicon-based, fluorine-based, or wax-based release agent can be used.

The metal tubular member is formed of an aluminum alloy, titanium, a titanium alloy, magnesium, a magnesium alloy, or the like.

Next, as a method of forming the WBL, it depends on the method of forming the bat. For example, a sheet-shaped prepreg is wound around a mandrel, then placed in a mold, and a pressure is applied from the inside of the cylindrical prepreg. In the internal pressure forming method of forming a desired bat shape by adding a prepreg forming an FRP layer, a mold release agent is applied to the inner surface of the metal tubular member, and inserted into a hitting portion. , Can be easily formed.

Alternatively, in the above internal pressure forming method,
After the prepreg forming the RP layer is wound, the release film is wound, and the metal tubular member is inserted into the hitting portion to form the RP layer.

As another method, a mandrel is covered with a reinforcing fiber in the form of a blade (bag) and placed in a mold.
In the resin transfer molding method (RTM method), in which an epoxy resin or polyester resin serving as a matrix resin is injected into a mold and cured, a mold is released onto the inner surface of a metal tubular member from above with a blade covered. The WBL can be formed between the metal tubular member and the FRP by applying the agent, inserting the agent into the hitting portion, and performing RTM molding.

In addition to the above-mentioned molding methods, the above-mentioned method is used for the filament winding molding method, the reaction injection molding molding method (RIM molding method), or the like. It is possible to form a WBL between the layers of the tubular member and the FRP and between the layers of the laminated FRP.

If the WBL is provided at a specific portion of the hitting portion except at both ends of the metal tubular member, both ends of the metal tubular member are fixed to the bat body. The tubular member does not rotate when hitting a ball.

The WBL may be provided on the entire circumference in the circumferential direction except for both ends of the metal tubular member as described above, but may be provided in a part in the circumferential direction, for example, at 45 ° in the ball hitting direction.
It can also be divided into two or more specific portions in the range of up to 180 ° or in the circumferential direction. In this way, if the ball is hit at a certain portion of the WBL, it rebounds greatly and the WB
If the ball is hit at a portion where there is no L, a bat that rebounds normally can be obtained. Further, the durability can be increased as compared with the case where the WBL is provided on the entire circumference.

When the metal tubular member is made of an aluminum alloy, the FRP in direct contact with the aluminum alloy is used.
If CFRP is used, electric corrosion is generated. Therefore, it is desirable to use GFRP as the FRP that comes into direct contact with the metal tubular member.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. In the embodiment of FIG. 1, a metal tubular member 3 is arranged over substantially the entire length of a hitting portion 2, and both ends of the metallic tubular member 3 are provided. In the embodiment of FIG. 2, the metal tubular member 3 is arranged in a part of the hitting portion 2, and both ends of the metal tubular member 3 are excluded. The WBL 4 is formed on the entire circumference in the circumferential direction. In addition, the length of both ends where the metal tubular member 3 is fixed to the bat body can be arbitrarily set. FIG. 3 is a cross-sectional view of a central portion of the metal tubular member 3 of FIGS. 1 and 2.

Further, as shown in FIG. 4, the WBL 4 is provided only in the range where the center angle θ in the ball hitting direction is 45 ° to 180 °, or as shown in FIG. 5, at two or more specific portions in the circumferential direction. It can be provided separately.

In the present invention, various combinations of GFRP, CFRP and the like of the bat body in which the FRP5 is laminated can be variously combined. Table 1 shows an embodiment of the FRP bat 1 shown in FIG. The metal tubular member 3 of the bat is made of a 7000 series aluminum alloy. The WBL 4 is formed by applying a release agent to the inner surface of the metal tubular member 3.

[0035]

[Table 1] In the above table, the symbols described for the types of lamination, GF indicates glass fiber, and CF indicates carbon fiber.

Next, the softball F according to the present invention is used.
Table 2 shows test results obtained by comparing an RP bat with a conventionally known FRP bat for softball and a metal bat for softball.

[0037]

[Table 2]

As shown in Table 2, in the bat having the hitting portion 2 having the WBL 4, the hitting portion 2 is easily deformed, the so-called trampoline effect is increased, and the resilience performance for flying the ball far away is reduced. Significantly improved.

On the other hand, regarding the impact resistance, the FR of the present invention was used.
The P bat 1 has excellent impact resistance equivalent to that of a metal bat. Therefore, the FRP bat 1 of the present invention
Is a high-performance bat that satisfies durability and also has excellent rebound performance.

The FRP bat 1 of the present invention may be an FRP bat 1 having a hollow portion as in the above embodiment, or a polyurethane, polyacrylonitrile or other foam synthetic resin core material (not shown). The FRP bat 1 having a solid portion interposed may be used.

[0041]

The present invention is embodied in the form described above and has the following effects.

By forming the WBL in the hitting portion, the flat stiffness of the bat is reduced, the so-called trampoline effect is generally increased, and the resilience performance of the ball to fly farther is greatly improved.

With respect to impact resistance, a metal tubular member is disposed on the surface of a hitting portion for hitting a ball, so that the same impact resistance as a metal bat is maintained, and the impact of the impact is directly applied to the FRP. Since it is not transmitted, generation of cracks and cracks, which are weak points of FRP, can be prevented.

Further, by changing the configuration of the FRP and the arrangement of the WBLs, various FRP bats having different resilience and impact resistance can be manufactured.

[0045]

[Brief description of the drawings]

FIG. 1 shows an embodiment in which a metal tubular member is arranged over substantially the entire length of a hitting portion.

FIG. 2 is an embodiment in which a metal tubular member is arranged in a part of a hitting portion.

FIG. 3 is a cross-sectional view of a central portion of the metal tubular member of FIGS. 1 and 2;

FIG. 4 is an explanatory view showing an embodiment of an FRP bat in which a WBL is interposed in a part of a hitting portion in a circumferential direction.

FIG. 5 is an explanatory view showing another embodiment of an FRP bat in which a WBL is interposed in a part of a hitting portion in a circumferential direction.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 FRP bat 2 Hitting part 3 Metal tubular member 4 WBL 5 FRP θ Central angle

Claims (5)

[Claims] 1. A bat in which a bat body is formed by laminating fiber reinforced plastics such as glass fiber reinforced plastic and carbon fiber reinforced plastic, wherein a metal tubular member is arranged on a surface layer of a hitting portion. An FRP bat for baseball or softball, wherein a weak boundary layer is provided between layers between the tubular member and the fiber reinforced plastic. 2. The baseball or softball FRP bat according to claim 1, wherein the weak boundary layer is provided between layers of fiber reinforced plastic. 3. The baseball or softball FRP bat according to claim 1, wherein the weak boundary layer is provided only in a specific portion between the layers. 4. The baseball or softball as claimed in claim 1, wherein the weak boundary layer is formed by laminating a film-like material. FRP bat. 5. The FRP for baseball or softball according to claim 1, wherein the weak boundary layer is formed by applying a release agent. Bat.