JP2022170798A - Tip center for bamboo sword, and bamboo sword - Google Patents

Abstract

To provide a bamboo sword that has an improved function of holding the tip shape of a split bamboo and an improved function of relaxing impact at a striking time.SOLUTION: A tip center 100 attached to the tip of a bamboo sword 1, formed by bundling cylindrically multiple split bamboos 10, includes an insertion part 110 inserted into a cylindrical internal space N, and multiple tabular projections 130 extended radially from the insertion part 110, and inserted between the multiple split bamboos 10.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a center that is installed at the tip of a bamboo sword used in kendo.

For example, a bamboo sword has a structure in which four pieces of split bamboo, which are split in the axial direction, are combined and bundled into a tubular shape. In the four split bamboos, the outer shape of the cross section orthogonal to the axial direction is nearly circular, and a circular or square inner space is formed on the center side. Toe cores made of rubber material are attached to the ends of the four split bamboos, and the outside is covered with toe leather. The center of the shinai not only plays a role in maintaining the shape of the shinai near the tip, but also has a function of softening the impact during use of the shinai.

FIG. 3(A) shows the structure of a conventional tip center Q. As shown in FIG. The conventional tip center Q consists of a cylindrical insertion portion Q1 that is inserted into the internal space from the tip side of the split bamboo, and a disk-shaped cover portion Q2 that expands in diameter so as to be continuous with the tip of the insertion portion Q1. have The lid portion Q2 abuts on the tip surfaces of the four split bamboos (see Patent Document 1, for example).

The diameter of the insertion portion Q1 is, for example, 6.0 mm, 7.5 mm, 9.0 mm, 12.0 mm, etc., and is appropriately selected according to the size of the internal space of the split bamboo.

Japanese Patent Application Laid-Open No. 09-10371

Since the material of split bamboo is often made of natural bamboo, the size and cross-sectional shape near the tip naturally vary. As a result, as shown in FIGS. 3(B) and 3(C), when inserting the tip center Q which becomes the insertion part Q1 having a diameter larger than the minimum inner diameter of the original internal space of the split bamboo W, the adjacent split bamboo W A gap S1 is formed between the side surfaces. Due to this gap S1, the split bamboo W moves in the circumferential direction M and collides directly with each other, so the shock absorbing function tends to deteriorate. In addition, the non-uniformity of the gap S1 degrades the original impact absorption function of the bamboo sword.

On the other hand, as shown in FIGS. 3(D) and 3(E), when inserting the tip center Q which becomes the insertion portion Q1 having a diameter smaller than the minimum inner diameter of the original inner space of the split bamboo W, the outer periphery of the insertion portion Q1 and A gap S2 is formed between the inner walls of the split bamboo W. Due to this gap S2, the split bamboo W moves in the radial direction, and adjacent split bamboo Ws are displaced in the radial direction.

In addition, as in these cases, if the impact mitigation function of the tip Q is insufficient, the tip of the split bamboo is likely to split due to the impact at the time of impact.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a centerpiece or the like that improves the function of retaining the shape of the tip of a split bamboo and the function of absorbing the impact at the time of impact.

The present invention, which achieves the above objects, is a center tip to be attached to the tip of a bamboo sword in which a plurality of split bamboos are bundled into a tubular shape, comprising an insertion portion inserted into the tubular inner space, and A tip center for a bamboo sword, characterized by comprising a plurality of plate-like projections extending radially and inserted between the plurality of split bamboos.

In relation to the tip center for a bamboo sword, the plate-like projection is characterized in that it spreads in the axial direction and the radial direction of the bamboo sword.

In relation to the tip center for a bamboo sword, the thickness of the plate-shaped projection in the circumferential direction of the bamboo sword is 0.2 mm or more.

In relation to the tip center for a bamboo sword, the thickness of the plate-like projection in the circumferential direction of the bamboo sword is 1.0 mm or less.

In relation to the tip center for a bamboo sword, the tip of the bamboo sword is further provided with a lid part that is continuously expanded in diameter from the tip of the insertion part and abuts on the tip of the split bamboo. The side edge is characterized by being independent of the lid.

In relation to the tip center for a bamboo sword, the plate-like protrusions are provided at equal intervals in the circumferential direction.

The present invention for achieving the above objects is characterized by comprising a plurality of split bamboos bundled into a tubular shape, and the above-mentioned tip center for a bamboo sword attached to the tips of the plurality of split bamboos. is.

ADVANTAGE OF THE INVENTION According to this invention, the excellent effect that the shape retention function of the tip of a split bamboo and the tip center etc. which improve the impact-absorbing function at the time of hitting can be obtained.

(A) is a front view of the bamboo sword of this embodiment, (B) is a front cross-sectional view enlarging the vicinity of the tip of the same bamboo sword, and (C) is a cross-sectional view taken along line CC in (B). , (D) are a right side view, a front view, and a left side view of the tip center installed in the bamboo sword. (A) A right side view, a front view, and a left side view showing a modification of the same center, and (B) is a cross-sectional view taken along line BB in (A). (A) is a right side view, a front view, and a left side view of a tip center installed in a conventional bamboo sword, and (B) is a front cross-sectional view enlarging the vicinity of the tip of the bamboo sword where a conventional tip center is installed. (C) is a cross-sectional view taken along line CC in (B), (D) is a front cross-sectional view enlarging the vicinity of the tip of a bamboo sword in which a conventional center point is installed, and (E) is ( D) is a cross-sectional view taken along line EE.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

1(A) to (C) show a bamboo sword 1 according to this embodiment. In this embodiment, for convenience of explanation, the axial direction J, the radial direction K, and the circumferential direction M are used with reference to the central axis line C of the bamboo sword 1 when explaining the directions. In some cases, the tip side in the axial direction J is called the "tip", and the handle side is called the "rear end".

The bamboo sword 1 consists of a plurality of split bamboos 10 (four here) obtained by splitting natural bamboo in the axial direction, a handle 14 attached to the rear end (hand end) of the split bamboo 10, and the split bamboo 10. a tip center 100 attached to the tip (point side) of the split bamboo 10, a tip leather 18 put on so as to cover the tip of the split bamboo 10 and the tip center 100, and a string-like core that bundles the split bamboo 10 in the middle of the axial direction J A knot 22, a string puller 26 continuously extending from the handle side to the tip side, a string 30 connecting the toe leather 18 and the string puller 26 while passing the middle tie 22, and the tip of the handle leather 14. It has a collar 34 and a collar stop 38 mounted near the edge. The length of the bamboo sword 1 is 3.4 shaku (3.4×30 cm), 3.6 shaku (3.6×30 cm), 3.7 shaku (3.7×30 cm), 3.8 shaku ( 3.8 x 30 cm) and 3.9 shaku (3.9 x 30 cm).

As shown in FIG. 1(C), the split bamboo 10 has a cross section perpendicular to the axial direction J that has a partial circular arc shape. A plurality of (four) split bamboos 10 are arranged in parallel along the circumferential direction M at equal intervals (90° phase intervals) to form a tubular structure as a whole. As a result, an internal space N (commonly called a tip hole) is formed by the plurality of split bamboos 10 . The split bamboo 10 is generally made of natural bamboo, but may be made of a carbon material or the like.

As shown in FIG. 1(D), the tip center 100 has an insertion portion 110 that is inserted into the tubular inner space N of the bamboo sword 1 from the tip side, and an insertion portion 110 that is inserted from the tip side (the tip side) of the insertion portion 110. It has a lid portion 120 that continuously expands in diameter, and plate-like protrusions 130 that extend radially from the insertion portion 110 . The centerpiece 100 is preferably made of an elastically deformable rubber material, such as natural rubber, synthetic rubber, or silicone rubber. It is also possible that the tip center 100 is made of plastic.

The length of the insertion portion 110 in the axial direction J is 2.0 cm or more and 5.0 cm or less, and is set to about 3.0 cm, for example. In addition, the diameter of the insertion portion 110 is 4.0 mm or more and 15.0 mm or less, and is set to 4.5 mm, 5.0 mm, 6.0 mm, 7.5 mm, 9.0 mm, 12.0 mm, etc. be done. This diameter is appropriately selected according to the minimum inner diameter of the internal space N of the actual bamboo sword 1 (the thickness of the split bamboo 10 in the radial direction K).

The lid portion 120 has, for example, a disc shape with a diameter of 20 mm or more, and is set to have a diameter of 15 mm, for example. The thickness of the lid portion 120 in the axial direction J is 2 mm or more, and is set to 5 mm, for example. As shown in FIG. 1B, the surface of the lid portion 120 facing the rear end side contacts the tip surface 10A of the split bamboo 10. As shown in FIG.

The plate-like projection 130 has a plate shape extending in the axial direction J and the radial direction K. As shown in FIG. Four plate-like protrusions 130 are provided at equal intervals (a phase difference of 90°) in the circumferential direction on the outer periphery of the insertion portion 110 . As shown in FIG. 1(C), each plate-shaped projection 130 is inserted between a plurality of split bamboos 10 . That is, the plate-shaped projection 130 is sandwiched between a pair of side surfaces (contact surfaces) 10B of the split bamboo 10 adjacent to each other.

The outer dimension H of the plate-shaped projection 130 in the radial direction K is, for example, 2.0 mm or more, preferably 5.0 mm or more, with the outer peripheral surface of the insertion portion 110 as the starting point. It is preferable that the smaller the diameter of the insertion portion 110 is, the larger the outer dimension H is set, and the larger the diameter of the insertion portion 110 is, the smaller the outer dimension H is set. At least a part of the outer edge (ridge line) 130A of the plate-like projection 130 in the radial direction K is preferably separated from the central axis C by 8.0 mm or more, more preferably by 1.0 mm or more. Furthermore, with the radius r of the lid portion 120 as a reference, the outer edge (ridge line) 130A of the plate-like projection 130 in the radial direction K is preferably separated from the center axis C by 0.8r or more, and more preferably, the outer circumference of the lid portion 120. It is preferable to reach the plane. As a result, the plate-shaped projection 130 can be prevented from being pinched by the side surfaces 10B of the split bamboo 10 and separated.

A thickness T of the plate-like projection 130 in the circumferential direction M is set to 0.2 mm or more, preferably 0.3 mm or more, and more preferably 0.4 mm or more. This thickness T can sufficiently secure the shock absorbing function. On the other hand, the thickness T of the plate-shaped projection 130 is preferably 1.0 mm or less, and desirably 0.8 mm or less. In this embodiment, the thickness T is set to 0.5 mm. If the thickness T is too large, the gap between the side surfaces 10B of the split bamboo 10 becomes too large, and the contact resistance between the side surfaces 10B during use becomes too small. The maximum length L of the plate-shaped projection 130 in the axial direction J is set to 10.0 mm or more, preferably 20.0 mm or more. This length L can further improve the impact absorption function.

Furthermore, the tip edge 130</b>B of the plate-shaped projection 130 in the axial direction is independent (separated) from the lid portion 120 . As a result, when the split bamboo 10 moves in the circumferential direction M, only the plate-shaped projection 130 sandwiched therebetween can freely follow. This leads to extension of the life of the leading center 100 .

According to the bamboo sword 1 of this embodiment, the tip of the split bamboo 10 is supported by the core 100 . At this time, since the plate-shaped projections 130 are interposed between the pair of side surfaces 10B of the adjacent split bamboos 10, the impact applied to the split bamboos 10 can be absorbed by the plate-shaped projections 130. - 特許庁In particular, when the split bamboo 10 is made of natural bamboo, its shape, width, thickness, etc. are uneven, but the plurality (four) split bamboos 10 are formed through the four plate-shaped projections 130. is continuous in the circumferential direction, the impact applied to the core 100 and the tips of the split bamboos 10 is evenly distributed to the plurality of split bamboos 10. - 特許庁As a result, the concentration of impact on a specific split bamboo 10 is avoided, so damage and deterioration of the split bamboo 10 can be suppressed.

Furthermore, since the plate-shaped projections 130 always ensure an appropriate interval near the tips of the four split bamboos 10, the side surfaces 10B of the split bamboos 10 are in proper contact with each other over the entire axial direction of the bamboo sword 1. do. As a result, when the split bamboo 10 bends during use, it is possible to exhibit strong elasticity and impact resistance while enhancing toughness by appropriate contact resistance.

In addition, in the tip center 100 of the above-described embodiment, the tip edge 130B of the plate-shaped projection 130 is independent (separated) from the lid portion 120, but the present invention is not limited to this. As shown, the tip edge 130B of the plate-shaped projection 130 may be integrated so as to be connected to the lid portion 120 .

It should be noted that the bamboo sword and the center of the present invention are not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

1 Shinai 10 Split bamboo 10A Tip face 10B Side face 14 Handle leather 18 Tip leather 26 String pull 30 String 34 Tsuba 100 Tip center 110 Insertion part 120 Lid part 130 Plate-like projection 130A Outer edge 130B Tip edge C Center axis

Claims (7)

A tip center attached to the tip of a bamboo sword in which a plurality of split bamboos are bundled in a cylindrical shape,
an insertion portion inserted into the cylindrical internal space;
A tip center for a bamboo sword, comprising: a plurality of plate-like projections radially extending from the insertion portion and inserted between the plurality of split bamboos. The plate-shaped projection is characterized by spreading in the axial direction and radial direction of the bamboo sword,
The tip center for a bamboo sword according to claim 1. The thickness of the plate-shaped projection in the circumferential direction of the bamboo sword is 0.2 mm or more,
The tip center for a bamboo sword according to claim 1 or 2. The thickness of the plate-shaped projection in the circumferential direction of the bamboo sword is 1.0 mm or less,
The tip center for a bamboo sword according to any one of claims 1 to 3. Furthermore, a lid portion is provided which expands in diameter continuously from the tip of the insertion portion and abuts on the tip of the split bamboo,
A tip side edge of the plate-shaped projection in the axial direction of the bamboo sword is independent of the lid,
The tip center for a bamboo sword according to any one of claims 1 to 4. The plate-like protrusions are provided at four equal intervals in the circumferential direction,
The tip center for a bamboo sword according to any one of claims 1 to 5. A plurality of split bamboo bundled into a cylinder,
A bamboo sword comprising the center for a bamboo sword according to any one of claims 1 to 6, which is attached to the tips of the plurality of split bamboos.

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