JP7060945B2 - Baseball bat - Google Patents

Description

Application of Article 30, Paragraph 2 of the Patent Act Announced at 2018 SPRING & SUMMER COLLECTION held from May 30, 2017 to July 14, 2017 (publications, etc.) October 27, 2017 to 2017 Wholesaled to each shipping destination (dealer) listed in the attached document "List of shipping date and shipping (selling) location" on November 28.

The present invention relates to a Japanese-style baseball bat having a tubular hitting portion laminated in a plurality of layers.

In the soft baseball bat as described above, by providing a weak boundary layer layer which is an adhesion inhibitory layer between the layers of the fiber reinforced plastic material in the hitting portion, the flatness is suppressed while suppressing the decrease in the flatness strength in the hitting portion. There is an FRP bat that improves the resilience performance while suppressing the decrease in durability by making it possible to improve the trampoline effect due to the decrease (see, for example, Patent Document 1).

Further, an elastic body having a storage elastic modulus of 0.01 MPa to 6 MPa is coated on the core portion of the bat body made of a material having the same rigidity as that of a conventional bat, and at least a part of the hitting portion is made of the elastic body. By forming the ball, the elastic deformation of the elastic body generated at the time of hitting suppresses the deformation of the ball, and the air resistance applied to the ball after hitting is reduced to extend the flight distance of the hit ball (for example, Patent Document). 2).

Japanese Unexamined Patent Publication No. 2000-20080 Japanese Unexamined Patent Publication No. 2004-275742

In the configuration described in Patent Document 1, since it is not considered to suppress the deformation of the ball that occurs at the time of hitting the ball, the ball is greatly deformed into a flat shape at the time of hitting the ball. Therefore, the air resistance applied to the ball after hitting the ball becomes large, which causes a decrease in the flight distance due to the stall of the hit ball.

In the configuration described in Patent Document 2, when the ball used is heavy or hard, the elastic body may be greatly elastically deformed at the time of hitting the ball, and the ball may reach the core portion of the bat body. In this case, since the core portion of the bat body is made of a highly rigid material as in the conventional bat, the ball is greatly deformed into a flat shape. Therefore, the air resistance applied to the ball after hitting the ball becomes large, which causes a decrease in the flight distance due to the stall of the hit ball. In addition, if the center of gravity of the bat deviates from the center of gravity of the ball at the time of hitting due to the ball reaching the core of the bat body having a small diameter and being deformed, the deformation of the ball at this time causes the center of gravity of the bat to be deformed. The amount of deviation of the center of gravity of the ball with respect to the ball increases, and the direction of hitting the ball tends to shift to the rear side.

In view of this situation, a main object of the present invention is to provide a soft baseball bat capable of extending the flight distance of a hit ball even when the ball used is heavy or hard.

The first characteristic configuration of the present invention is
In the baseball bat
Equipped with a tubular hitting part laminated in multiple layers,
The hitting portion is a tubular foam body laminated on the outer periphery of the hitting portion side cylindrical body of a bat body having a grip side tubular body and a hitting portion side tubular body. Has an elastic body including
The ball striking portion side tubular body is formed in a high repulsion region in which the intermediate portion in the longitudinal direction of the bat is laminated in a plurality of layers in a non-adhesive state, and the laminated portions at both ends in the longitudinal direction of the bat are adhered. It is in.

According to this configuration, when the ball is caught by the hitting portion at the time of hitting, first, the elastic body is elastically deformed by contact with the ball to hold the ball, so that the ball is suppressed from being deformed and the ball is cylinderd. It will reach the high resilience region of the shape. In the high-resilience region, a plurality of layers are laminated in a non-adhesive state, so that the trampoline effect is improved by the decrease in the flat rigidity while suppressing the decrease in the flat strength, and the repulsion performance is enhanced. Therefore, when the ball reaches the high repulsion region, the high repulsion region bends and deforms so as to receive the ball, suppresses the deformation of the ball, and then repels the ball due to its repulsion performance. In addition, the elastic body repels the ball with its elasticity along with this rebound.
As a result, when the center of gravity of the ball is captured by the axis of the hitting portion at the time of hitting, the deformation of the ball that occurs at the time of hitting is suppressed, and the increase in air resistance applied to the ball due to the deformation is suppressed. In addition, the synergistic effect of the trampoline effect in the high repulsion region and the elasticity of the elastic body can be obtained, so that the flight distance of the hit ball can be significantly extended.
In addition, when the center of gravity of the ball deviates slightly from the axis of the hitting portion at the time of hitting, the deformation of the ball that occurs at the time of hitting is suppressed, so that the air resistance applied to the ball due to the deformation increases and the axis of the bat. In addition to being able to suppress an increase in the amount of deviation of the ball center of gravity with respect to the ball, the synergistic effect of the trampoline effect in the high repulsion region and the elasticity of the elastic body is obtained, so that the hitting direction is easily displaced to the rear side. It is possible to extend the flight distance of the hit ball while suppressing the hitting ball.
As a result, it is possible to provide a soft baseball bat that can extend the flight distance to the front of the hit ball when the ball is caught by the hitting portion even when the used ball is heavy or hard. ..

The second characteristic configuration of the present invention is
The elastic body has an elastic layer having a thickness of 3 to 10 mm.

According to this configuration, the deformation of the ball due to the elastic deformation of the elastic body is satisfactorily suppressed while suppressing the decrease of the trampoline effect in the high repulsion region due to the small outer diameter of the tubular body. It can be carried out.
On the other hand, if the thickness of the elastic layer in the elastic body is less than 3 mm, the outer diameter of the tubular body becomes large, so that the trampoline effect in the high repulsion region can be easily obtained. Deformation suppression is reduced.
Further, when the thickness of the elastic layer in the elastic body exceeds 10 mm, the suppression of the deformation of the ball due to the elastic deformation of the elastic body is improved, but the outer diameter of the tubular body becomes smaller, so that the trampoline effect in the high repulsion region is obtained. In addition to being difficult to obtain, the strength of the bat is lowered, and the durability of the bat is likely to be lowered.
That is, according to this configuration, both the trampoline effect in the high repulsion region and the elasticity of the elastic body can be satisfactorily obtained while preventing the durability of the bat from being lowered, and the synergistic effect of these can be used to fly the hit ball. You can extend the distance.

The third characteristic configuration of the present invention is
The elastic body has an elastic layer having a C hardness of 55 to 83.

According to this configuration, when the ball is caught by the hitting portion, a state in which the elastic body is elastically deformed by contact with the ball and the ball is held can be obtained satisfactorily.
On the other hand, when the C hardness of the elastic layer in the elastic body is less than 55, the elastic body becomes too soft, the holding action of the ball by the elastic body is reduced, and the ball is easily deformed.
Further, when the C hardness of the elastic layer in the elastic body exceeds 83, the elastic body becomes too hard, and the ball is likely to be deformed due to contact with the elastic body.
That is, according to this configuration, the deformation of the ball that occurs when the ball is caught by the hitting portion can be suppressed more effectively, and the air resistance applied to the ball due to the deformation increases and the hitting ball is hit. It is possible to more effectively suppress the decrease in flight distance due to stall.

The fourth characteristic configuration of the present invention is
The point is that the thickness of the ball-hit portion side cylindrical body is 1.8 to 4.5 mm.

According to this configuration, the inner diameter of the tubular body including the high repulsion region can be made as large as possible, thereby improving the trampoline effect by reducing the flat rigidity while suppressing the decrease in the flat strength in the high repulsion region. It is possible to improve the repulsion performance in the high repulsion region.

Overall view of the baseball bat An exploded perspective view of a baseball bat Longitudinal cross-sectional view of the hitting part side of a baseball bat Enlarged vertical cross-sectional view of the main part in the hitting part Explanatory drawing showing change with time of hitting part shape at the time of hitting Cross-sectional plan view showing the molding state of the elastic body

Hereinafter, embodiments of a Japanese-style baseball bat to which the present invention has been applied will be described with reference to the drawings.
In this embodiment, an example is a soft baseball bat in which FRP (fiber reinforced plastic) is used as a main material, but the soft baseball bat is mainly made of a metal such as titanium, a titanium alloy, or an aluminum alloy. It may be adopted as a material, and FRP or the above-mentioned metal may be fitted to the main material as a tubular reinforcing material. Further, the softball baseball bat may be a combination in which a main material of a different material is adopted and combined on the grip side and the hitting portion side.

As shown in FIGS. 1 to 3, the softball bat (hereinafter referred to as a bat) 1 exemplified in this embodiment has a bat body 2 made of FRP and a grip attached to a grip side end portion of the bat body 2. The end 3, the end cap 4 attached to the tip of the bat body 2, the tubular elastic body 5 laminated on the ball striking portion side of the bat body 2, and the grip side and the ball striking portion side of the bat body 2. It is provided with a tapered sleeve 6 that fills the step between them.

The bat body 2 is independent of a grip-side tubular body 7 having a widened tip 7A and a small diameter, and a large-diameter tubular body 8 having a narrowed diameter portion 8A. It is a molded two-piece structure. Then, the enlarged diameter portion 7A of the grip side tubular body 7 and the reduced diameter portion 8A of the ball striking portion side tubular body 8 are in a state where the outer peripheral surface of the enlarged diameter portion 7A is in surface contact with the inner peripheral surface of the reduced diameter portion 8A. It is glued with.
The adhesive length W between the enlarged diameter portion 7A and the reduced diameter portion 8A in the longitudinal direction of the bat is preferably 30 to 120 mm, and in the present embodiment, the one set to the optimum 60 mm as the adhesive length W is exemplified. ing.
The bat body 2 may be one in which the grip-side tubular body 7 and the ball striking portion-side tubular body 8 are integrally formed.

Although not shown, the grip side tubular body 7 is formed by laminating a sheet-shaped prepreg composed of carbon fiber and glass fiber impregnated with a thermosetting resin such as epoxy resin into a mandrel by a predetermined laminating method. After winding to a uniform layer thickness as a whole, the pressurizing tube is inserted into a cylindrical prepreg instead of a mandrel, placed in a two-piece mating mold, and heat-cured. As a result, the grip-side tubular body 7 is formed so as to have higher rigidity and strength than the ball striking portion-side tubular body 8.

As shown in FIG. 4, in the molding of the ball striking portion side tubular body 8, first, the above-mentioned sheet-shaped prepreg is used as the first layer 8a on a mandrel (not shown), and the film-like prepreg is used as the first layer 8a and is uniformly uniform as a whole by a predetermined laminating method. After winding to the layer thickness, the OPP film (biaxially stretched polypropylene film) is wound as the first adhesion inhibitory layer 8b on the surface of the first layer 8a, leaving both ends of the first layer 8a in the longitudinal direction of the bat. .. Next, the above-mentioned sheet-shaped prepreg is used as the second layer 8c and wound around the surfaces of both ends of the first layer 8a and the first adhesion-inhibiting layer 8b to a uniform layer thickness as a whole by a predetermined laminating method. , The OPP film is wound as the second adhesion inhibitory layer 8d on the surface of the second layer 8c, leaving both ends of the second layer 8c in the longitudinal direction of the bat. Then, the above-mentioned sheet-shaped prepreg is wound around the surfaces of both ends of the second layer 8c and the second adhesion-inhibiting layer 8d as the third layer 8e by a predetermined laminating method to obtain a uniform layer thickness as a whole. The pressurizing tube is inserted into the cylindrical first layer 8a instead of the mandrel, placed in a two-divided bonding die, and heat-cured.
The layer thickness of the first layer 8a, which is the innermost layer of the ball striking portion side tubular body 8, is preferably 1.0 to 2.5 mm, and more preferably 1.6 to 2.1 mm. In the present embodiment, the layer thickness of the first layer 8a is set to 1.9 mm, which is the optimum layer thickness. The layer thickness of the second layer 8c, which is the intermediate layer of the ball striking portion side tubular body 8, is preferably 0.6 to 1.2 mm, and in the present embodiment, the optimum layer thickness of the second layer 8c is 0. The one set to 9 mm is exemplified. The layer thickness of the third layer 8e, which is the outermost layer of the ball striking portion side tubular body 8, is preferably 0.2 to 0.8 mm, and in the present embodiment, the optimum layer thickness of the third layer 8e is 0. The one set to 5 mm is exemplified.
As a result, the ball striking portion side tubular body 8 has a thin cylindrical shape with a layer thickness of about 3.3 mm, and is flattened by being laminated in three layers in a non-adhesive state in the middle portion in the longitudinal direction of the bat. It has a high repulsion region 8f of a triple tube structure in which a decrease in flat rigidity is achieved while suppressing a decrease in strength.
Incidentally, the layer thickness of the ball striking portion side cylindrical body 8 is preferably 1.8 to 4.5 mm, and more preferably 2.4 to 4.1 mm.

The ball striking portion side tubular body 8 has a double tube structure laminated in two layers in a non-adhesive state or a quadruple tube laminated in four layers in a non-adhesive state in the middle portion in the longitudinal direction of the bat. It may be molded so as to have a high repulsion region 8f such as a structure.

That is, as shown in FIGS. 2 to 3, the bat 1 includes a grip side tubular body 7 and a ball striking portion side tubular body 8 in which the bat body 2 has higher rigidity and strength than the ball striking portion side tubular body 8. The bat at the time of hitting a ball by appropriately adhering the enlarged diameter portion 7A of the grip side tubular body 7 and the reduced diameter portion 8A of the hitting portion side tubular body 8 in a two-divided structure formed by being divided into two parts. The power loss due to the reverse warp of 1 can be suppressed, and the swing power can be efficiently transmitted to the bat 1. Further, when the axis of the bat 1 deviates from the center of gravity of the ball 10 (see FIG. 5) at the time of hitting a ball, the impact is difficult to be transmitted from the hitting portion side tubular body 8 to the grip side tubular body 7. The impact is transmitted to the hand holding the grip-side tubular body 7, which makes it less likely that the hand becomes numb.
Then, as shown in FIGS. 3 to 5, the ball hitting portion side tubular body 8 has a thin cylindrical shape with a layer thickness of 3.3 mm and has a high repulsion region 8f having low flat rigidity, so that the height generated at the time of hitting the ball is increased. The flight distance of the hit ball can be extended by the trampoline effect (see FIG. 5) in the repulsion region 8f.

In each of the first layer 8a, the second layer 8c, and the third layer 8e of the grip side tubular body 7 and the ball striking portion side tubular body 8, any or all of them are sheet-shaped. Instead of the prepreg, a tape-shaped prepreg may be wound around a mandrel to a uniform layer thickness to form a mandrel. Further, in addition to the OPP film, the adhesion-inhibiting layers 6b and 6d of the ball-beating portion side tubular body 8 may have a mold, for example, a commercially available wrap film for food packaging made of polyvinylidene chloride, a silicon rubber sheet, or the like. Various products can be adopted as long as they have the property of not melting when heated and cured.

As shown in FIGS. 2 and 4 to 6, in the ball striking portion side tubular body 8, the elastic body 5 is laminated on the outer periphery thereof, whereby the tubular striking portion 9 laminated in a plurality of layers is formed. There is. The elastic body 5 is an elastic layer 5a made of urethane foam in which PU (polyurethane) is foamed as a rubber-based or synthetic resin-based material having high hitting resilience, and a TPU sheet (thermoplastic) of the same type as the elastic layer 5a. It has a coating layer 5b made of a polyurethane sheet).
For the elastic layer 5a, for example, a foam obtained by foaming EVA, EEA, polyethylene, polypropylene, isoprene, EPDM, polyamide, polyvinyl chloride, polyvinylidene chloride, ABS, ionomer, butadiene rubber, etc. is adopted. As the coating layer 5b, a rubber-based or synthetic resin-based sheet of the same type as the elastic layer 5a may be adopted.

As shown in FIG. 6, for molding the elastic body 5, first, two transparent TPU sheets having a thickness of 0.5 to 1.0 mm are prepared, and the product name, pattern, etc. are printed on these TPU sheets from the back. After printing, both ends of the two TPU sheets are fused and turned inside out to form the coating layer 5b. Next, the coating layer 5b is installed together with the core 12 in the two-divided combined mold 11, the PU is poured between the coating layer 5b and the core 12, and the PU is foamed to form the elastic layer 5a. It is done through processes such as.
The layer thickness of the elastic layer 5a is 3.0 to 10.0 mm in the ball striking region 5c (see FIG. 4) of the elastic body 5 laminated on the high repulsion region 8f of the ball striking portion side tubular body 8. It is preferable, and in particular, since it is more preferably 3.0 to 7.0 mm, in the present embodiment, the one set to 5.0 mm is exemplified.

Although not shown, the elastic body 5 is attached to the ball striking portion side tubular body 8 by wrapping a double-sided tape around the surface of the ball striking portion side tubular body 8 and then using an organic solvent such as benzine or white gas. By temporarily disabling the adhesive surface of the double-sided tape and fitting the elastic body 5 from the grip side of the bat body 2 to the ball striking portion side tubular body 8, the elastic body 5 is laminated on the ball striking portion side tubular body 8. It can be installed in the same state. Then, after the elastic body 5 is attached to the ball striking portion side tubular body 8 in this way, the sleeve 6 is attached to the bat body 2 so as to fill the step between the grip side tubular body 7 and the ball striking portion side tubular body 8. Various attachment steps are performed, such as attaching by adhering, attaching the grip end 3 to the grip side end of the butt body 2, and attaching the end cap 4 to the tip of the butt body 2.

As shown in FIG. 6, in the coating layer 5b of the elastic body 5, a pair of groove portions 5d extending along the longitudinal direction of the bat 1 are formed so as to function as a flexible portion that allows the expansion of the diameter of the coating layer 5b. As a result, the elastic body 5 is attached to the ball striking portion side tubular body 8 of the bat body 2 by fitting and laminating the elastic body 5 from the grip side of the bat body 2 to the ball striking portion side tubular body 8. Can be facilitated.

As a result of measuring the C hardness of the elastic body 5, it is preferable that the C hardness of the elastic body 5 at the central portion in the longitudinal direction of the bat is 55 to 83 when the elastic layer 5a is directly measured, particularly 55. It is more preferably to 63, and in addition, the C hardness at a position 150 mm from the tip of the bat 1 is 58 to 60, and the C hardness at a position 200 mm from the tip of the bat 1 is 59 to 61. It is more preferable to have.
Further, the C hardness when measured from above the coating layer (TPU sheet) 5b is preferably 67 to 85, more preferably 67 to 75, and in addition, from the tip of the bat 1. It is more preferable that the C hardness at the position of 150 mm and the C hardness at the position 200 mm from the tip of the bat 1 are 70 to 72, respectively.

As a result of measuring the elastic modulus of the elastic body 5, the dynamic loss elastic modulus of the number of test pieces n1 in the elastic body 5 was 0.331 MPa, and the dynamic loss elastic modulus of the number of test pieces n2 was 0.361 MPa. The dynamic loss elastic modulus of the number of test pieces n3 is 0.358 MPa, and their average value is 0.350 MPa. That is, the dynamic loss elastic modulus of the elastic body 5 is preferably 0.3 to 0.4 MPa, and more preferably 0.33 to 0.37 MPa.
Further, the dynamic storage elastic modulus of the number of test pieces n1 in the elastic body 5 is 1.99 MPa, the dynamic storage elastic modulus of the number of test pieces n2 is 2.15 MPa, and the dynamic storage elastic modulus of the number of test pieces n3. Is 2.21 MPa, and their average value is 2.12 MPa. That is, the dynamic storage elastic modulus of the elastic body 5 is preferably 1.7 to 2.5 MPa, and more preferably 1.9 to 2.3 MPa.
Here, as a test adjustment method, a urethane portion (thickness of about 4 mm) was sampled from the product and adjusted to a thickness of 2 mm with a slicer. Then, a strip-shaped test piece having a width of 3 mm was produced by cutting.
The shape of the test piece is 30 mm in length × 3 mm in width × 2 mm in thickness, the test variable is 3, the measurement mode is tension mode, the distance between jigs is 20 mm, the frequency is 100 Hz, and the measurement temperature is 20 ° C. The load was 9.8 × 10 ^ (-2) N, and the vibration displacement was 20 μm.
The tester used was a dynamic viscoelasticity measuring device (DMA + 1000) manufactured by METRAVIB.

With the above configuration, when the ball 10 is caught by the ball hitting portion 9 at the time of hitting the ball, the bat 1 according to the present invention first comes into contact with the ball 10 as shown in FIGS. 5A to 5B. By holding the ball 10 while the elastic body 5 elastically deforms, the ball 10 reaches the high repulsion region 8f of the ball hitting portion side tubular body 8 while the deformation of the ball 10 is suppressed. Then, when the ball 10 reaches the high repulsion region 8f, as shown in FIGS. 5 (b) to 5 (c), the high repulsion region 8f bends and deforms so as to receive the ball 10 and suppresses the deformation of the ball 10. After that, the ball 10 will be repelled by its repulsive performance. Further, with this rebound, the elastic body 5 repels the ball 10 with its elasticity.
As a result, when the center of gravity of the ball 10 is captured by the axial center of the hitting portion 9 at the time of hitting, the deformation of the ball 10 that occurs at the time of hitting is suppressed, and the air resistance applied to the ball 10 due to the deformation is increased. In addition to being able to suppress the above, the synergistic effect of the trampoline effect in the high repulsion region 8f and the elasticity of the elastic body 5 can be obtained, so that the flight distance of the hit ball can be significantly extended.
Further, when the center of gravity of the ball 10 is slightly deviated from the axis of the hitting portion 9 at the time of hitting the ball, the deformation of the ball 10 that occurs at the time of hitting is suppressed, so that the air resistance applied to the ball 10 due to the deformation is increased. In addition to being able to suppress an increase in the amount of deviation of the ball center of gravity with respect to the axis of the bat 1, the trampoline effect in the high repulsion region 8f and the synergistic effect of the elasticity of the elastic body 5 are obtained, so that the hitting direction can be changed. It is possible to extend the flight distance of the hit ball while suppressing the tendency to shift to the rear side.
As a result, even when the softball 10 becomes heavy and hard due to the change of the officially recognized ball, if the ball 10 is caught by the hitting portion 9 at the time of hitting, the flight distance to the front of the hitting ball can be extended.

Since the thickness of the elastic layer 5a in the elastic body 5 is 3 to 10 mm, it is possible to prevent the outer diameter of the ball striking portion side tubular body 8 from becoming smaller, whereby the ball striking portion side tubular body can be prevented from becoming smaller. While suppressing the decrease in the strength of the bat 1 and the trampoline effect in the high repulsion region 8f due to the small outer diameter of 8, the deformation of the ball 10 due to the elastic deformation of the elastic body 5 is satisfactorily suppressed. It can be carried out.
As a result, both the trampoline effect in the high repulsion region 8f and the elasticity of the elastic body 5 can be satisfactorily obtained while preventing the durability of the bat 1 from being lowered, and the flight distance of the hit ball can be increased by the synergistic effect thereof. Can be stretched.

Further, since the C hardness of the elastic layer 5a in the elastic body 5 is 55 to 83, when the ball 10 is caught by the hitting portion 9, as shown in FIGS. 5A to 5B, when the ball 10 is caught by the ball striking portion 9. A state in which the elastic body 5 holds the ball 10 while elastically deforming due to contact with the ball 10 can be obtained satisfactorily.
As a result, the deformation of the ball 10 that occurs when the ball 10 is caught by the hitting portion 9 can be more effectively suppressed, and the air resistance applied to the ball 10 increases due to the deformation, and the hit ball stalls. It is possible to more effectively suppress the decrease in flight distance due to this.

Moreover, since the thickness of the ball striking portion side tubular body 8 is 1.8 to 4.5 mm, the inner diameter of the ball striking portion side tubular body 8 including the high repulsion region 8f can be made as large as possible. It is possible to improve the trampoline effect by reducing the flat rigidity while suppressing the decrease in the flatness strength in the high repulsion region 8f, and it is possible to improve the repulsion performance in the high repulsion region 8f.

[Another Embodiment]
In the above embodiment, as the tubular body (ball hitting portion side tubular body) 8, an FRP-made one having a high repulsion region 8f of a multi-tube structure in which FRP is laminated in a plurality of layers in a non-adhesive state is exemplified. However, the tubular body 8 is not limited to this, and the tubular body 8 has a high repulsion region 8f of a multi-tube structure in which metals such as titanium, titanium alloys, aluminum alloys, etc. are laminated in a plurality of layers in a non-adhesive state. It may be made of a metal having a metal, or may have a high repulsion region 8f of a multi-tube structure in which different materials such as FRP and the above-mentioned metal are laminated in a plurality of layers in a non-adhesive state.

5 Elastic body 5a Elastic layer 8 Cylindrical body 8f High repulsion region 9 Hitting part

Claims (4)

Equipped with a tubular hitting part laminated in multiple layers,
The hitting portion is a tubular foam body laminated on the outer periphery of the hitting portion side cylindrical body of a bat body having a grip side tubular body and a hitting portion side tubular body. Has an elastic body including
The ball striking portion side tubular body is formed into a high repulsion region in which the intermediate portion in the longitudinal direction of the bat is laminated in a plurality of layers in a non-adhesive state, and the laminated portions at both ends in the longitudinal direction of the bat are adhered to the soft type. Baseball bat. The softball baseball bat according to claim 1, wherein the elastic body has an elastic layer having a thickness of 3 to 10 mm. The softball baseball bat according to claim 1 or 2, wherein the elastic body has an elastic layer having a C hardness of 55 to 83. The softball baseball bat according to any one of claims 1 to 3, wherein the ball-hit portion side cylindrical body has a thickness of 1.8 to 4.5 mm.

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