JP2001157725A - Wooden baseball bat and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wooden baseball bat and its manufacturing method, which is hard to break while in use, durable, can hit a ball in a long distance and is easily manufactured by crushing the wood surface to harden it. SOLUTION: After a wooden material is processed into a bat, a ball-hitting part 4 of the wooden bat 1 is sprayed with abrasives 5 by blast apparatus 6. To spray the abrasives 5 evenly all over the surface of the bat, the wooden bat 1 is rotated to be sprayed all around and a concave portion is formed on the surface of the ball-hitting part 4 of the wooden bat 1. Then the concave portion is filled with a synthetic resin and hardened by heating or at room temperature. then the surface of the bat 1 is polished with sand paper and formed into its completed shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wooden bat (hereinafter, referred to as a wooden bat) used for baseball and softball, and a method for manufacturing the same.

[0002]

2. Description of the Related Art In a wooden bat, repeated hitting causes peeling or cracking from a grain or the like during use, resulting in loss or breakage. Conventionally, in order to solve these problems, various methods have been proposed for reinforcing the wood of a wooden bat with a resin.

For example, in a wooden bat in which a concave portion formed on the surface of the bat is filled with a synthetic resin or the like, as disclosed in Japanese Utility Model Publication No. 50-20773, the outer periphery of the molded bat body extends from the tip to the hitting portion. A baseball bat is known in which a groove is formed along the annual ring and filled with an adhesive such as a synthetic resin.

Japanese Utility Model Publication No. 35-14714 discloses a structure of a baseball bat in which a number of small holes are provided at an appropriate depth in a hitting portion and a synthetic resin liquid is injected and hardened into the holes. .

[0005]

However, the wooden bat obtained by such a conventional method has the following drawbacks.

That is, in the method disclosed in Japanese Utility Model Publication No. 50-20773, in which a groove is formed along the line of the annual ring on the outer periphery from the tip of the molded bat body to the hitting portion, there is no description in the text. It is very common to use a wood graining machine that rotates a drum-shaped wire brush, which is often used in the above-mentioned processing, to bring it into contact with the surface of wood, and to move and use it. According to this method, the groove is formed by scraping off the weak portion of the wooden surface by the wire brush, and then the wooden bat is reinforced by filling the groove with a synthetic resin or the like. Therefore,
The wooden surface was simply roughened by the wire brush before injecting the resin, and was not intended to strengthen the wood itself, so that during use the resin was not filled except for the grooves, There has been a problem that a breakage occurs from a void or the like generated during resin filling.

In a baseball bat disclosed in Japanese Utility Model Publication No. 35-14714, an infinite number of small holes are provided at an appropriate depth on the outer periphery of a hitting portion, and synthetic resin is injected into the hole and hardened. The bat is characterized by providing holes everywhere on the wooden surface of the bat, and does not take into account the fact that the wooden material has an uneven structure in which a hard portion and a soft portion are mixed. Therefore, in the soft and weak portion of the woody material, there is a problem that a crack or the like is generated from a portion where the resin is not injected, and the portion is broken.

In view of the above problems, the present invention crushes the wooden surface to obtain a hardened surface, hardly breaks during use, is durable, has a long flight distance, and is suitable for manufacturing. It is an object of the present invention to provide a wooden bat that does not require any labor and a method for manufacturing the same.

[0009]

Therefore, in order to achieve the above object, an object of the present invention is to provide a wooden bat in which a concave portion formed on the outer peripheral surface of a bat is filled with a synthetic resin or the like. Is a wooden baseball bat formed by spraying a blast material.

[0010] The invention of claim 2 provides a step of injecting a blasting material onto the surface of a hitting portion of a wooden baseball bat to form a concave portion, a step of filling the concave portion with a resin and curing the resin, and thereafter, Polishing the bat surface to finish the bat surface.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to preferred embodiments which are described in detail with reference to the drawings. That is, FIG. 1 shows a perspective view of the wooden bat of the present embodiment, FIG. 2 shows an enlarged sectional view of the wooden bat of the present embodiment, and FIG. 3 explains a method of manufacturing the wooden bat of the present embodiment. FIG. 4 shows an explanatory view, and FIG. 4 shows an enlarged sectional view of a wooden bat of another embodiment.

As shown in FIGS. 1 to 3, the wooden bat of this embodiment has a structure in which a concave portion 2 formed on the surface of a wooden bat 1 is filled with a synthetic resin 3 or the like.
Are formed by spraying the blast material 5. That is, the wooden surface is crushed by spraying the blast material 5, and the surface is hardened by forming the concave portion 2, so that the wooden surface is hardly broken during use and the durability is improved.

To manufacture the wooden bat 1 of this embodiment,
As shown in FIGS. 2 and 3, first, after processing wood into a bat shape, a blasting device 6 or the like injects a shot material 5 onto the hitting portion 4 of the wooden bat 1. Next, in order to evenly inject the blast material 5 over the entire surface of the bat, the wooden bat 1 is sprayed over the entire circumference while rotating, so that the concave portion 2 is formed on the surface of the hitting portion 4 of the wooden bat 1. Then, the recess 2
Is filled with a synthetic resin 3 or the like, and cured by heating or at room temperature. Thereafter, the surface of the wooden bat 1 is polished with a sandpaper or the like to finish the shape of the final bat. Therefore,
Since a consumable part such as a mold is not required, the work of spraying the blast material 5 further presses a weak part of the wood of the wooden bat 1, so that the entire wood surface is crushed and the recess 2 is formed. In this way, the production efficiency is improved without requiring any trouble in the production. Further, if the recess 2 is filled with a synthetic resin 3 or the like, the bat can be further strengthened.
This improves the durability of the bat.

[0014] In the material of the projectile, alumina,
Examples include ceramic beads, glass beads, plastic beads, spheres of aluminum and its alloys, and among these, the type of wood, the degree of crushing,
Can be selected by setting the depth. In the present embodiment, a duck material was used as the bat material, and aluminum oxide particles were used as the material of the blast material 5.

The aluminum oxide particles of this embodiment used had a particle size of 200 μm to 300 μm.
If the particle size of the blast material is less than 200 μm,
This is because the effect of pressing and crushing such that the shot material is buried between the wood fibers cannot be obtained. In addition, in the case of a particle diameter of 300 μm or more, the mass of the particles becomes heavy, and there is a possibility that wooden fibers on the wooden surface may be destroyed.
This is because it is impossible to evenly press the coarse and fine portions of the wood fiber.

In the injection pressure in this embodiment, in order to obtain a wooden surface crush suitable for hitting a wooden bat by injection of aluminum oxide particles,
Injection was performed at 0.55 MPa to 0.65 MPa. 0.55
If the pressure is less than Mpa, the injection pressure is weak and a sufficient pressing effect cannot be obtained. If the pressure exceeds 0.65 MPa, the injection pressure is strong and the wood fibers may be broken.

In this embodiment, the wooden surface is pressed and crushed by the injection of the blast material, so that the entire surface of the bat is evenly crushed, so that the solid density of the wooden surface layer is increased. In addition, the weak and soft portion of the wooden surface became a concave portion, and the concave portion was filled with a synthetic resin or the like, whereby a wooden bat having a hard wooden surface was obtained.

In the present invention, the wooden bat in which the concave portion formed on the surface of the bat is filled with a synthetic resin or the like may have a circular cross section 7 as shown in FIG. As described above, the concave portion 2 formed by the injection may not be completely filled with the synthetic resin 3 or the like, and the concave and convex section 8 in which the concave portion 2 remains on the surface may be used.

[0019]

As described above, in the present invention, by spraying a blasting material onto the surface of a wooden bat, the entire wooden surface is crushed, the solid density of the wooden surface layer is increased, and the surface is hardened. It is possible to provide a wooden bat which is effective, durable and has a long flight distance. Further, by filling the resin into the recess formed by the injection pressure, the resin can be hardened by the resin in addition to the hardening of the wooden surface, so that it is hard to break and the durability is further improved.

Further, in the present invention, the wooden surface is crushed by pressing the wooden surface by the projecting operation of the blasting material, and the concave portion is formed, so that consumable parts such as a mold are not required. Since the blasting material is evenly sprayed on the wooden surface, it exerts the effect of evenly pressing even uneven surface conditions in which hard and soft parts of wood are mixed, making the manufacturing operation extremely easy. And the process does not take much time.

Further, since the concave portion formed by the injection of the blast material has a smooth surface concave portion, the resin filling property is good, and the effect of preventing the occurrence of voids is also exerted, and the durability of the wooden bat is improved. It is to let.

In the case of the shot material, the particle size is 200 μm.
m-300 μm aluminum oxide spray pressure 0.55
By spraying at a pressure of MPa to 0.65 MPa, a wooden crushed surface suitable for hitting a wooden bat can be obtained, thereby improving durability and also having an effect of improving a flight distance. is there.

[Brief description of the drawings]

FIG. 1 is a perspective view of a wooden bat according to an embodiment.

FIG. 2 is an enlarged cross-sectional view of the wooden bat of the embodiment.

FIG. 3 is an explanatory view showing a method of manufacturing the wooden bat of the embodiment.

FIG. 4 is an enlarged sectional view of a wooden bat showing another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wooden bat 2 Concave part 3 Synthetic resin 4 Hitting part 5 Projection material 6 Blast device 7 Circular section 8 Irregular section

Continued on the front page (72) Inventor Kazuhiko Shindome 3877-8 Takada, Yoro-cho, Yoro-gun, Gifu Pref.

Claims (2)

[Claims] 1. A wooden baseball bat wherein a concave portion formed on the outer peripheral surface of the bat is filled with a synthetic resin or the like, and the concave portion is formed by spraying a blast material. 2. A step of injecting a blasting material onto the surface of a hitting portion of a wooden baseball bat to form a concave portion, filling the concave portion with a resin and curing the resin, and thereafter, polishing the bat surface by polishing. A method of manufacturing a wooden baseball bat, comprising a step of finishing.