Hitting part and bat using same

Abstract

To provide a ball hitting part capable of reducing energy loss in the ball hitting part, and improving repulsive force.SOLUTION: A ball hitting part 5 includes: a core material 7 decentered and arranged on one side in a radial direction; a first elastic body 15 having one side part 19 in the radial direction supported by the core material 7, and the other side part 21 in the radial direction facing in the radial direction to the core material 7 through a space part 23, and having relatively small elastic hysteresis; and a second elastic body 17 covering outside in the radial direction of the other side part 21 of the first elastic body 15 to form a ball hitting surface 5a, and having relatively large elastic hysteresis.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a ball-hitting portion having an elastic body and a bat for ball games using the same. [Background technology]

[0002] An example of a conventional bat is described in Patent Document 1. This bat has a cylindrical base member that serves as a core material, and a cylindrical elastic body that is integrated with the portion of the base member that will serve as the ball-hitting portion.

[0003] In this conventional bat, the elastic body deforms when the ball is hit, suppressing deformation of the ball, and when the elastic body returns to its original shape, it applies a repulsive force to the ball, thereby improving the flight distance of the hit ball.

[0004] However, conventional bats use viscoelastic materials such as polyurethane foam as the elastic body, which results in significant energy loss and limits the repulsive force that can be generated. As a result, conventional bats have a limit to how far the ball can travel. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-19236 Summary of the Invention [Problem to be solved by the invention]

[0006] The problem to be solved was that the energy loss at the hitting point was large, which limited the generation of rebound force. [Means for solving the problem]

[0007] The present invention provides a hitting portion of a bat for ball games, comprising: a core material positioned eccentrically on one radial side; a first elastic body having one radial side supported by the core material and the other radial side facing the core material with a space therebetween, the first elastic body having relatively small elastic hysteresis; and a second elastic body covering the radial outside of the other side of the first elastic body to form a hitting surface, the second elastic body having relatively large elastic hysteresis.

[0008] The present invention also provides a bat having the above-described ball-hitting portion. [Effects of the Invention]

[0009] The present invention can reduce energy loss in the entire ball-hitting portion and improve repulsion force by combining a first elastic body with a relatively small elastic hysteresis and a second elastic body with a relatively large elastic hysteresis.

[0010] Moreover, in the present invention, the deformation stroke of the first elastic body is increased by the large space created by eccentrically positioning the core material, thereby increasing elastic energy and further improving the repulsive force. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a perspective view showing a bat according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a longitudinal cross-sectional view of the bat of FIG. [Figure 3] 3 is a cross-sectional view showing the ball-hitting portion of the bat taken along line III-III in FIG. 2. FIG. [Figure 4] 4 is a perspective view showing a portion of the core material of the bat of FIG. 2. FIG. [Figure 5] 5(A) and (B) are cross-sectional views showing the relationship between the bat and the ball when hitting the ball, with FIG. 5(A) being an example and FIG. 5(B) being a comparative example. [Figure 6] FIG. 6 is a cross-sectional view showing the ball-hitting portion of a bat according to a modification of the first embodiment. [Figure 7]FIG. 6 is a cross-sectional view showing the ball-hitting portion of a bat according to another modification of the first embodiment. [Figure 8] FIG. 8 is a cross-sectional view showing a bat according to a second embodiment of the present invention. [Figure 9] 9 is a perspective view showing a portion of the core of the bat of FIG. 8. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0012] The objectives of reducing energy loss in the hitting area and improving the generated repulsion force were achieved by eccentrically positioning the core material in the hitting area, which combines a first elastic body with a relatively small elastic hysteresis and a second elastic body with a relatively large elastic hysteresis.

[0013] As shown in FIGS. 1 to 9, the ball hitting portion 5 of the bat 1 for ball games of the present invention includes a core material 7, a first elastic body 15, and a second elastic body 17.

[0014] The core material 7 is disposed eccentrically on one radial side. The first elastic body 15 has one radial side portion 19 supported by the core material 7 and another radial side portion 21 radially facing the core material 7 with a space 23 between them, and has relatively small elastic hysteresis. The second elastic body 17 covers the radial outside of the other side portion 21 of the first elastic body 15 to form the ball striking surface 5a, and has relatively large elastic hysteresis.

[0015] The second elastic body 17 may have any shape as long as it can form the ball striking surface 5a, but may be cylindrical in shape and contain the first elastic body 15 and the core material 7 therein.

[0016] The second elastic body 17 may also be joined to the core material 7 on one side in the radial direction.

[0017] The first elastic body 15 may have any shape as long as it has one radial side portion 19 and the other radial side portion 21, but may also be annular and arranged in parallel with the core material 7. In this case, a circumferential portion of the first elastic body 15 may constitute the one radial side portion 19.

[0018] Instead of being arranged in parallel as described above, the first elastic body 15 may be a cantilevered plate member arranged along the axial direction, with one axial side joined to the core material 7. In this case, one axial side of the first elastic body 15 constitutes one side portion 19, and the other axial side of the first elastic body 15 constitutes the other side portion 21. [Example]

[0019] [Bat structure] Fig. 1 is a perspective view showing a bat according to Example 1 of the present invention. Fig. 2 is a longitudinal sectional view showing the bat of Fig. 1. Fig. 3 is a transverse sectional view showing the ball-hitting portion of the bat along line III-III of Fig. 2. Fig. 4 is a perspective view showing a part of the core material of the bat of Fig. 2.

[0020] Bat 1 of this embodiment is used for ball games such as baseball and softball, and includes grip portion 3 and ball-hitting portion 5.

[0021] The grip portion 3 is the portion that is gripped by the batter and is made up of a part of the core material 7 .

[0022] The core material 7 is a hollow rod-like body. This core material 7 has a circular cross-sectional shape and a constant wall thickness. However, the wall thickness of the core material 7 can be made thinner or thicker in parts. Also, although the cross-sectional shape of the core material 7 is constant from the distal end to the proximal end, it can also be made different in shape by changing the diameter in parts. Furthermore, the cross-sectional shape of the core material 7 is not limited to a circle, and other shapes such as an ellipse can be adopted, and it may also be solid.

[0023] The material of the core material 7 is fiber reinforced plastic (FRP), and in this embodiment, carbon fiber reinforced plastic (CFRP). However, the material of the core material 7 is not limited to FRP, and metal, wood, etc. can also be used.

[0024] Core 7 integrally comprises grip portion 3, hitting area 9, and head portion 11 from the base end to the tip end in the axial direction. However, one, two, or all of grip portion 3, hitting area 9, and head portion 11 may be configured as separate members, and these separate members may be integrally joined to form core 7. The axial direction is the direction along the axis of bat 1 and includes a direction slightly oblique to the axis.

[0025] Grip portion 3 is a cylindrical portion that is gripped by the batter. In this embodiment, grip portion 3 is formed into a hollow rod shape with a circular cross section corresponding to the shape of core material 7. Grip tape 3a is wrapped around grip portion 3. A grip end 3b that protrudes radially is provided at the base end of grip portion 3. A ball-hitting area 9 is integrally provided at the tip of grip portion 3. The radial direction refers to the direction along the diameter of bat 1, but also includes a direction slightly oblique to the diameter.

[0026] The ball-hitting area 9 is part of the core material 7 that, together with the elastic member 13, constitutes the ball-hitting area 5, and is formed in the shape of a hollow rod with a circular cross section. The cross section of the ball-hitting area 9 is not limited to a circular shape and can be other shapes. For example, the cross section of the ball-hitting area 9 may be asymmetrical between one radial side and the other radial side, elliptical, or the like.

[0027] The hitting area 9 is disposed eccentrically to one side in the radial direction. That is, the center O2 of the hitting area 9 (core material 7) is disposed at a position offset in the radial direction from the center O1 of the hitting portion 5.

[0028] The eccentricity of the ball-hitting area 9 is gradually increased from the base end toward the tip end, and the amount of eccentricity is constant where the outer diameter of the ball-hitting area 5 is approximately constant. This constant amount of eccentricity is set according to the amount of deformation of the other side portion 21 of the first elastic body 15, which will be described later. The eccentricity of the ball-hitting area 9 may also be increased in a crank shape.

[0029] A head portion 11 is integrally provided at the tip of the ball-hitting area 9. The head portion 11 is formed in a disk shape. The head portion 11 bulges out radially from the ball-hitting area 9. The outer diameter of the head portion 11 is approximately the same as the outer diameter R of the ball-hitting area 5.

[0030] The ball-hitting portion 5 is configured by attaching an elastic member 13 to the ball-hitting region 9 of the core material 7. The elastic member 13 deforms when hitting the ball B, thereby suppressing deformation of the ball B and applying a repulsive force to the ball B. The ball B is a rubber ball. The elastic member 13 in this embodiment includes a first elastic body 15 and a second elastic body 17.

[0031] The first elastic body 15 is a member with a relatively small elastic hysteresis, and is elastically deformed when hitting the ball to generate a repulsive force with little energy loss.

[0032] Elastic hysteresis refers to the occurrence of energy loss due to a loop formed in a cycle of loading and unloading within the elastic range of the stress-strain relationship. This elastic hysteresis can be appropriately set by the material, shape, etc. of the first elastic body 15.

[0033] In this embodiment, the material of the first elastic body 15 is CFRP, which is the same material as the core material 7. However, the first elastic body 15 can also be formed from a material different from that of the core material 7.

[0034] The first elastic body 15 is formed in a ring shape and arranged in parallel in the ball-hitting area 9. In this embodiment, the first elastic body 15 is preferably provided in an area that includes at least the impact center, or so-called sweet spot, of the ball-hitting area 5 in the axial direction. In this embodiment, the first elastic body 15 is formed in a cylindrical shape that extends axially from the front to the rear of the sweet spot.

[0035] In this embodiment, the cross-sectional shape of first elastic body 15 is formed into an arc shape having a C-shaped channel. The arc shape of first elastic body 15 has an outer diameter larger than that of ball-hitting area 9 of core material 7 and a constant thickness. The center O3 of first elastic body 15 is radially offset from the center O1 of ball-hitting area 5 and the center O2 of ball-hitting area 9.

[0036] However, the center O3 of first elastic body 15 may coincide with the center O1 of the ball-hitting portion 5. Furthermore, the thickness of first elastic body 15 may vary in either or both the circumferential direction and the axial direction.

[0037] One radial side portion 19 of the first elastic body 15 is a discontinuous end portion of a C-shaped channel and is integrally joined to the hitting area 9 of the core material 7. This gives the first elastic body 15 a closed annular shape. As a result, one radial side portion 19 of the first elastic body 15 is supported by the hitting area 9 of the core material 7, and the other radial side portion 21 of the first elastic body 15 faces the hitting area 9 of the core material 7 in the radial direction with a space 23 between them.

[0038] The one side portion 19 is a portion located on one radial side of the first elastic body 15, and the other side portion 21 is a portion located on the other radial side of the first elastic body 15. When the first elastic body 15 is annular as in this embodiment, the one side portion 19 is configured by a portion in the circumferential direction, and the other side portion 21 is configured by a portion in the circumferential direction located on the opposite side of the one side portion 19 in the radial direction.

[0039] The support of the one side portion 19 against the core material 7 is sufficient if the one side portion 19 can be received by the core material 7 in the radial direction and radial movement of the first elastic body 15 can be suppressed. For this reason, the one side portion 19 does not have to be integral with the core material 7, and can be formed as a separate piece from the core material 7 and either joined or not joined so as to abut against it.

[0040] Furthermore, the support position (bonding position) of one side portion 19 of core material 7 in this embodiment is a position slightly offset to one side from the radial center O2 of ball-hitting area 9. However, this bonding position can be changed as appropriate depending on the elasticity of first elastic body 15, the size of space portion 23, etc.

[0041] The other side portion 21 of the first elastic body 15 is part or all of the arc-shaped portion in the range radially facing the ball-hitting area 9 of the core material 7. The other side portion 21 is capable of radially displacing within the range of the space 23 toward the core material 7 due to the elastic deformation of the first elastic body 15.

[0042] In this embodiment, the eccentricity of the hitting area 9 of the core 7 allows a large space 23 to be secured, thereby increasing the amount of deformation of the other side portion 21 of the first elastic body 15 until it reaches the core 7. In other words, the flexibility of the first elastic body 15 can be made according to the amount of eccentricity of the core 7, and the first elastic body 15 can be actively elastically deformed.

[0043] In addition, in this embodiment, the first elastic body 15 is annular and arranged in parallel with the core material 7 along the axial direction, and a portion of the circumferential direction forms one side portion 19, making it easy to secure a space portion 23 and also making it easy to support one side portion 19 of the first elastic body 15 on the core material 7.

[0044] The second elastic body 17 covers the radially outer side of the other side portion 21 of the first elastic body 15 to form the ball-striking surface 5a, and is a member with relatively large elastic hysteresis. This second elastic body 17 suppresses deformation of the ball B by compressive deformation and bending when hitting the ball. The ball-striking surface 5a refers to the surface of the ball-striking section 5 that is intended to be hit. The elastic hysteresis of the second elastic body 17 can be set as appropriate by the material, shape, etc. of the second elastic body 17.

[0045] In this embodiment, second elastic body 17 is cylindrical and encloses first elastic body 15 and ball-hitting area 9 of core material 7. As a result, second elastic body 17 is provided around the entire circumference of ball-hitting area 5, forming ball-hitting surface 5a around the entire circumference of ball-hitting area 5. Therefore, in this embodiment, it is possible to hit ball B around the entire circumference of ball-hitting area 5.

[0046] However, second elastic body 17 may be an arc-shaped plate or the like provided on a portion of the circumference of ball-hitting portion 5. In this case, second elastic body 17 is positioned at least on other side portion 21 of first elastic body 15 to form ball-hitting surface 5a.

[0047] The outer diameter of the second elastic body 17 gradually increases from the base end toward the tip end in the axial direction, and remains approximately constant at the tip end. The axial tip end of this second elastic body 17 abuts against the head portion 11 of the core material 7 in the axial direction, and the base end is prevented from coming off in the axial direction by a collar 25. In this state, the inner peripheral surface of the second elastic body 17 is fixed to the first elastic body 15 and the core material 7 by an appropriate fixing means such as an adhesive.

[0048] By this fixation, second elastic body 17 is joined to core material 7 on one radial side. The joining of second elastic body 17 to core material 7 can be ensured by the eccentricity of core material 7. By being joined to core material 7 on one radial side in this manner, second elastic body 17 can be reliably compressed and deformed and bent to suppress deformation of ball B when ball B collides with the other radial side.

[0049] The second elastic body 17 in this embodiment has a cylindrical cross section with a substantially uniform thickness in the circumferential direction. However, the thickness of the second elastic body 17 may vary in the circumferential direction. The thickness refers to the radial dimension between the inner and outer peripheries of the second elastic body 17.

[0050] The material of the second elastic body 17 is a viscoelastic body such as foamed polyurethane resin. However, the material of the second elastic body 17 may be any material that can suppress deformation with respect to the ball B, and may be appropriately set in relation to the ball B, etc.

[0051] The surface of the second elastic body 17 is covered with a skin material 27. The skin material 27 improves durability against impact with the ball B. The skin material 27 in this embodiment is formed in the shape of a cylindrical film made of thermoplastic resin such as polyurethane film. The skin material 27 may be omitted.

[0052] [Bat Action] 5(A) and (B) are cross-sectional views showing the relationship between the bat and the ball when hitting the ball, with FIG. 5(A) showing the present embodiment and FIG. 5(B) showing a comparative example.

[0053] In addition, the comparative example of Figure 5 (B) has a circular first elastic body 15 embedded in a second elastic body 17, and the core material 7, first elastic body 15, and second elastic body 17 arranged concentrically.

[0054] In this embodiment, when the hitting portion 5 collides with the ball B, part of the kinetic energy of the ball B is converted into deformation energy of the hitting portion 5. This deformation energy is the sum of the deformation energy of the second elastic body 17, which has high viscous damping, and the deformation energy of the first elastic body 15, which has low damping.

[0055] As the conversion of the kinetic energy of ball B into deformation energy progresses, ball B decelerates, and the deformation energy accumulated in the first elastic body 15 and the second elastic body 17 of the hitting area 5 is converted back into the kinetic energy of ball B as ball B stops.

[0056] 5(A), when ball B collides with the other radial side of the hitting area 5, the other radial side of the hitting area of second elastic body 17 is initially pressed by ball B and is mainly compressed and deformed. This compressive deformation suppresses deformation of ball B when it collides with the hitting area 5.

[0057] At this time, the second elastic body 17 is coupled to and received by the core material 7 on one side in the radial direction, and therefore can be reliably compressed and deformed on the other side in the radial direction in response to the impact of the ball B.

[0058] When the second elastic body 17 is compressed between the ball B and the first elastic body 15, the pressing force of the ball B is transmitted via the compressed portion to the other side portion 21 of the first elastic body 15. This pressing force elastically deforms the first elastic body 15, and the other side portion 21 is displaced to one side in the radial direction so as to narrow the space portion 23.

[0059] At this time, the eccentricity of the ball-hitting area 9 of the core 7 ensures a large space 23, which increases the amount of elastic deformation of the other side portion 21 of the first elastic body 15 until it reaches the core 7. This reduces the amount of compressive deformation of the second elastic body 17.

[0060] Therefore, in this embodiment, viscous damping due to compressive deformation of second elastic body 17 is suppressed, and energy loss can be reduced when the deformation energy accumulated in ball-hitting portion 5 is converted into kinetic energy of ball B. As a result, bat 1 of this embodiment has a good resilience characteristic value in ball-hitting portion 5, and can improve the flight distance of ball B.

[0061] Furthermore, with bat 1 of this embodiment, by using one radial side of ball-hitting portion 5, only second elastic body 17 can be deformed, and a different hit can be obtained from the other radial side.

[0062] In the comparative example, when ball B hits the ball-hitting portion 5 on the other radial side, the other radial side of the second elastic body 17, which is the point of impact, is initially pressed by ball B and undergoes compressive deformation, as in the example.

[0063] When the second elastic body 17 is compressed between the ball B and the first elastic body 15, the pressing force of the ball B is transmitted to the other side portion 21 of the first elastic body 15 via the compressed portion. At this time, in the comparative example, the first elastic body 15 moves as a whole to the other radial side and undergoes almost no elastic deformation. As a result, the ball B is deformed or the amount of compression of the second elastic body 17 increases.

[0064] Therefore, in the comparative example, viscous damping due to deformation of ball B or compressive deformation of second elastic body 17 increases, and the energy loss when deformation energy is accumulated in hitting portion 5 and converted into kinetic energy of ball B increases.

[0065] [Variations] FIG. 6 is a cross-sectional view showing the ball-hitting portion 5 of bat 1 according to a modified example.

[0066] In the modification shown in FIG. 6, the cross section of the first elastic body 15 is annular, and the core material 7 is bonded to the inner surface of one side portion 19.

[0067] FIG. 7 is a cross-sectional view showing the ball-hitting portion 5 of bat 1 according to another modification.

[0068] In the modification shown in Figure 7, the cross section of first elastic body 15 is semicircular, and core material 7 is bonded to the outer surface of one side portion 19. First elastic body 15 may also be circular. In this modification, the other side portion 21 of first elastic body 15 faces the ball-hitting area 9 of core material 7 with one side portion 19 interposed therebetween, with a space 23 formed between them.

[0069] In this way, the other side portion 21 only needs to face the core material 7 with the space portion 23 therebetween, and the form of facing does not matter whether it is direct facing with no intervening member or indirect facing with an intervening member.

[0070] The modifications of FIGS. 6 and 7 can also achieve the same effects as those of the first embodiment. [Example]

[0071] Figure 8 is a cross-sectional view of a bat according to Example 2 of the present invention. Figure 9 is a perspective view of a portion of the core material of the bat in Figure 8. Note that Example 2 has the same basic configuration as Example 1, so the same reference numerals are used for corresponding components and redundant explanations will be omitted.

[0072] In Example 2, the first elastic body 15 is formed of a cantilevered plate material. Also, in this example, the collar 25 is provided integrally with the core material 7. The rest is the same as Example 1. However, the collar 25 may be formed separately from the core material 7, as in Example 1.

[0073] First elastic body 15 is provided along the axial direction, and one axial side is joined to core material 7. One axial side of first elastic body 15 forms one radial side portion 19, and the other axial side forms other radial side portion 21. Note that one axial side of first elastic body 15 is the base end side of bat 1, but it may also be the tip end side. In this case, the other axial side of first elastic body 15 is the base end side of bat 1.

[0074] The one side portion 19 in this embodiment is an inclined plate portion that is integrally connected to the collar 25 and gradually transitions radially outward toward the tip side. The one side portion 19 can also be provided along the core material 7.

[0075] The other side portion 21 is a plate portion provided along the core material 7 as a whole. In cross section, this other side portion 21 is formed in an arc shape that curves along the inner peripheral surface of the second elastic body 17. The other side portion 21 may be a flat plate, a wavy plate, or a collection of multiple rod-shaped or linear bodies.

[0076] In this embodiment, when the hitting area 5 collides with the ball B, the second elastic body 17 is compressed on the other radial side, and the first elastic body 15 elastically deforms with one side portion 19 as a fulcrum, thereby displacing the other side portion 21 so as to narrow the space portion 23 between the hitting area 9 of the core material 7 in the radial direction.

[0077] As a result, the present embodiment can also achieve the same effects as the first embodiment. [Explanation of symbols]

[0078] 1 bat 5 Ball batting section 5a Ball hitting surface 7 Core material 15 First Elastic Body 17 Second Elastic Body 19 One side 21 Other side 23 Space section

Claims

1. A hitting portion of a bat for a ball game, a core material disposed eccentrically on one side in the radial direction; a first elastic body having one radial side supported by the core material and another radial side facing the core material with a space therebetween, the first elastic body having a relatively small elastic hysteresis; a second elastic body that covers the radially outer side of the other side portion of the first elastic body to form a ball striking surface and has a relatively large elastic hysteresis; A hitting area equipped with

2. The ball hitting portion of claim 1, the second elastic body is tubular and contains the first elastic body and the core material; Hitting club.

3. The ball hitting portion of claim 2, The second elastic body is coupled to the core material at one side in the radial direction. Hitting club.

4. The ball hitting portion of any one of claims 1 to 3, The first elastic body is annular and arranged in parallel with the core material, and a part of the first elastic body in the circumferential direction constitutes the one side portion. Hitting club.

5. The ball hitting portion of any one of claims 1 to 3, the first elastic body is a cantilevered plate member provided along the axial direction and connected to the core member at one side in the axial direction, the one side in the axial direction constituting the one side portion and the other side in the axial direction constituting the other side portion, Hitting club.

6. A bat having the ball-hitting portion of any one of claims 1 to 5.

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