JP2002191724A - Gut protective body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gut protective body which is excellent in durability without breaking even when a gut is strung by a high tension, and in addition, can manifest favorable elastic characteristics at the time of hitting. SOLUTION: A comparatively large window hole 13 is formed in the region of a band section 10 between cylindrical sections 9 which become a location wherein at least the gut is strung while being folded back, from among gut protective members 12 comprising the upper layer section of this gut protective body. Then, a flexible expanded section 14, which is integrally formed on the upper surface of a band-form base 8 comprising the lower layer section, is expand-formed from the window hole 13 to the outside of the band section 10 by going through the window hole 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gut protector mounted on a racket frame.

[0002]

2. Description of the Related Art Conventionally, racket frames have been formed using materials such as wood and metal. However, at present, various characteristics such as toughness, rigidity and repulsion required for racket frames are satisfied. In addition, a racket frame made of a fiber-reinforced resin has come to occupy the mainstream because of a large degree of freedom in design such that a required shape is easily obtained.

Normally, this type of racket frame has a hitting portion 31, a grip portion 32, and a shaft portion 33 connecting the hitting portion 31 and the grip portion 32, as shown in FIGS. Outer shell layer 34 made of fiber reinforced resin
And a number of gut insertion holes 37 are formed in the hitting portion 31 of the racket frame so as to penetrate the outer peripheral surface 35 and the inner peripheral surface 36. . The outer peripheral surface 35 of the hitting portion 31
The gut protection groove 38 is recessed, and the gut protection groove 38 and each gut insertion hole 37 are provided with:
The gut protection groove 38 and a gut protection body 41 having a band portion 39 and a tube portion 40 fitted into the gut insertion hole 37 are mounted. A gut 43 made of a material such as nylon, sheep, whale muscle, or the like is inserted to form a striking surface 44.

[0004] Generally, the gut 43 is stretched
The gut protection body 41 is formed by a method called mechanical tension using a string machine or hand tension using a winding rod.
The operation of pulling the gut 43 inserted through the hole 42 of the cylindrical portion 40 with a desired tension and then fixing the gut 43 is sequentially and repeatedly performed into the hole 42 of the adjacent cylindrical portion 40. At that time, as shown in FIG. 13, the gut 43 straddles between the holes 42 of the adjacent cylindrical portions 40 and bends in a state near a right angle near the band-side opening of the hole 42. It is gut 4 in this state because it is stretched
When tension is applied to 3, the stress concentrates on the band-side opening region Ra of the hole 42 of the gut protection body 41 with which the gut 43 contacts. Therefore, when the gut 43 is to be stretched with a relatively large tension, or when the gut protection body 41 is
In the case where the thickness of the gut protection body 41 is thin, there is a problem that the above-described region Ra of the gut protection body 41 is crushed or broken by the gut 43 and is damaged.

Further, between the adjacent cylindrical portions 40, the gut 43 is not always in close contact with the outer surface of the band portion 39 of the gut protection body 41, but is in a state in which a slight floating t occurs from the outer surface. Therefore, due to the presence of the floating t of the gut 43, when the ball is hit, the gut 43 of the portion where the floating t is generated is extended and instantaneously collides with the outer surface of the band portion 39, causing unpleasant vibration. There was also a problem that noise and sound were generated.

Conventionally, in order to solve such a problem, for example, in Japanese Utility Model Laid-Open Publication No. Sho 61-16171, a large number of holes are drilled in a racket frame as shown in FIGS. 14 (a) and 14 (b). In a gut protection body 47 composed of a cylindrical diaper 45 inserted into each of the gut insertion holes and a long strip 46 integrally formed at one end of the diaper 45, An arc-shaped bulge 48 is provided on the surface not provided with the eyelet 45 at a portion between the openings of the eyelet 45 and through which the stretched gut 43 passes.
Gut protection body 47 configured to integrally form
Are proposed and known.

[0007]

As described above, in the conventional gut protector, the arcuate bulge is provided at the folded portion of the gut between the fitting openings, so that the gut passing through the portion is provided. The bend becomes a gradual state, and the stress applied from the gut when the gut is stretched is received and dispersed not only by the band-side opening area of the hole provided in the buckle but also by the arc-shaped bulge. Therefore, the strength of the folded portion of the gut of the gut protection body was increased, and it was possible to prevent the gut protection body from being damaged even if the gut was repeatedly stretched with high tension many times. Also, at the same time, between the adjacent eyelet openings,
Since the gut is stretched in close contact with the bulge of the gut protection body, it is possible to prevent troubles such as generation of unpleasant vibration and sound when hitting the ball.

However, on the other hand, this type of gut protector has a structure in which the gut is always supported in a close contact state by the bulge, and as shown in FIG. When the ball is pulled in the in-plane direction (the direction of the arrow) of the hitting portion, there is no play in which the gut 43 extends (the tension of the gut 43 hardly loosens). It is predicted that it depends only on the elasticity (elongation) of the material itself and the elasticity of the racket frame itself. Therefore, when hitting, the shot feeling is "hard" and not only causes discomfort to the player, but also has a drawback that the resilience decreases because sufficient elastic properties cannot be expected. In addition, since the ball is released quickly upon hitting the ball (the "bite" of the ball against the gut 43 is deteriorated), the controllability is reduced and a problem that it is difficult to apply a good spin to the ball is caused. Met.

As shown in FIG. 15, if the gut protector 47 having the above structure is made of a soft material having elasticity, the bulge 48 is moved in the in-plane direction by the tension of the gut 43 when hit. In this case, good elastic characteristics can be obtained by exciting elastic deformation, but in this case, the gut protection body 47 itself becomes brittle, and in particular, the band material side opening region Ra of the hole 42 of the gut protection body 47. In addition, it is expected that the fitting portion region Rb in contact with the opening end of the gut insertion hole that opens on the inner peripheral surface side of the hitting portion will be easily damaged by repeated use.

In view of the above-mentioned problems, the present invention has excellent durability without breaking even if the gut is stretched with high tension, and has good elastic properties when hit. To provide a gut protector that can be expressed

[0011]

In order to achieve the above object, the present invention has the following arrangement. That is, the gut protective body according to claim 1 of the present invention is a belt-shaped gut protective body made of a soft synthetic resin material provided with a large number of through holes that match the outer peripheral surface side openings of the gut insertion holes penetrating the inner and outer peripheral surfaces of the hitting portion. A substrate,
A gut protective body comprising: a plurality of cylindrical portions that are superposed on the surface of the band-shaped base material and are inserted into respective through holes; and a gut protecting member including a band portion that connects the plurality of cylindrical portions. Further, at least a part of the band-shaped base material is bulged from a window formed in a band portion of the gut protection member.

A second aspect of the present invention is the gut protection body according to the first aspect, wherein the window is formed at a portion where the gut between the adjacent cylindrical portions is folded and stretched. It is assumed that.

According to a third aspect of the present invention, there is provided the gut protection body according to the first or second aspect, wherein a bulging portion to be inserted into the window hole is integrally formed on a surface of the band-shaped base material corresponding to the window hole. It is characterized in that it is formed in a uniform manner.

According to a fourth aspect of the present invention, there is provided the gut protection body according to the third aspect, wherein the bulging portion is a bulge penetrating the window hole and exposing to the outside. .

According to a fifth aspect of the present invention, there is provided the gut protection body according to the fourth aspect, wherein the bulging portion is formed in an arc shape straddling an arch between adjacent cylindrical portions. It is.

According to a sixth aspect of the present invention, there is provided the gut protection body according to the first aspect, wherein the gut protection member has a bending elastic modulus of 5%.
It is characterized by being formed from a relatively hard material of 000 kg / cm ^{2 to} 15000 kg / cm ² .

According to a seventh aspect of the present invention, there is provided the gut protective body according to the first aspect, wherein the band-shaped base material has a flexural modulus of 1000.
and it is characterized in that it is formed from a relatively soft material ^{kg / cm 2 ~4000kg / cm 2} .

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is an external view of the gut protection body of the present embodiment, FIG. 2 is an exploded explanatory view of the gut protection body of the embodiment, and FIG. 3 is an end surface of a main part in an area AA of FIG. FIG.

That is, the gut protection body 1 of the present embodiment is similar to that of FIG.
As shown in FIG. 3 to FIG. 3, a gut insertion hole 6 provided along the bottom wall 5 of the gut protection groove 4 formed on the outer peripheral surface 3 of the hitting portion 2 of the racket frame and drilled in the hitting portion 2. And a band-shaped base material 8 made of a soft synthetic resin provided with a large number of through-holes 7 corresponding to the opening on the outer peripheral surface side of the base material. And hitting part 2
The plurality of cylindrical portions 9 inserted into the gut insertion holes 6 and the band portions 10 connecting the plurality of cylindrical portions 9 to each other. It has a two-layer structure including a gut protection member 12 integrally provided with an ear portion 11 that covers a part or the whole of the outer peripheral surface 3.

In the gut protection body 1 of this embodiment,
The gut protection member 1 forming an upper layer of the gut protection body 1
2, a relatively large window hole 13 is formed at least in the region of the band portion 10 between the cylindrical portions 9 where the gut is folded and stretched, and the band-shaped base material 8 forming a lower layer portion from the window hole 13 is formed. A soft bulging portion 14 integrally formed on the upper surface is configured to bulge out of the band portion 10 through the window hole 13.

The bulging portion 14 bulging from the window hole 13
Is formed so as to straddle the adjacent tube portions 9 in an arch shape so as to receive the folded portion of the gut stretched between the adjacent tube portions 9 and to make the bending of the gut gentle. And the height thereof is the highest in the central region between the cylindrical portions 9.

In the gut protection body 1 of this embodiment, as shown in FIG. 3, when the gut protection member 12 and the band-shaped base material 8 are superimposed, the gut protection member 12 is provided on the gut protection member 12 forming the upper layer. The formed cylindrical portion 9 is formed in the through hole 7 of the band-shaped base material 8 forming a lower layer portion, and the bulging portion 14 provided on the upper surface of the band-shaped base material 8 is formed in the window hole 13 of the gut protection member 12. Are engaged with each other, so that the connection between the two is strong and can be accurately combined without causing any misalignment.

Further, in the gut protection body 1, FIG.
As shown in the figure, the gut 15 straddled between the adjacent tubular portions 9 when the gut is stretched, the band-side opening region of each adjacent tubular portion 9 and the arc-shaped top surface of the bulging portion 14. To be supported in contact. Therefore, the stress applied from the gut 15 is received and dispersed not only by the band-side opening region of the adjacent tubular portion 9 but also by the arc-shaped top surface of the bulging portion 14 as in the related art. Even when the gut 15 is stretched with high tension, the stress applied to the gut protection body 1 is extremely small.

As shown in FIG. 4B, at the time of hitting, the soft bulging portion 14 receiving the gut 15 outside the band portion 10 causes the soft bulging portion 14 to move in the in-plane direction due to stress applied at the time of hitting. (In the direction of the arrow) to be deformed.
To give the ball a moderate elasticity by temporarily loosening the
Good resilience, controllability, and soft feel at impact can be exhibited. On the other hand, the gut 15
The portion other than the bulging portion 14 (the tubular portion 9 and the band-side opening region of the tubular portion 9) that is in contact with the swelling portion 14 is made of a relatively hard material. However, there is no problem that damage is easily caused.

The elasticity obtained by the bulging part 14 is as follows.
Although it depends on the material and shape of the bulging part 14 itself,
The higher the height of the bulging portion 14, the better the characteristics can be exhibited. In particular, the gut protection body 1 of the present embodiment is configured to have a height substantially equal to the depth of the gut protection groove 4. It is possible to make the height higher than this, but in this case, the bulging portion 14 protrudes outside the frame beyond the gut protection groove 4 and rubs the racket frame against the ground during play. In such a case, there is a risk that the bulging portion 14 or the gut 15 stretched over the bulging portion 14 may be worn out. For this reason, the height of the bulging portion 14 is
The gut protection groove 4 is preferably formed to have a depth lower than the depth of the gut protection groove 4. More specifically, the height is such that when the gut 15 is stretched, the folded portion of the gut 15 is substantially housed inside the gut protection groove 4. More desirably, it is formed.

In order to manufacture the gut protection body 1 of this embodiment, the gut protection member 12 and the band-shaped base material 8 are injection-molded in advance by using separate molds, and are molded. It is formed by combining and polymerizing both members. In addition, as shown in FIGS. 5 (a) and 5 (b), an injection molded product of the gut protection member 12 which has been separately molded in advance is incorporated into a mold 16 having a cavity of the gut protection body 1. Thereafter, a method of integrally forming the gut protection body 1 by injection-molding a soft synthetic resin material into the cavity 17 for forming the band-shaped base material of the cavity, or a reverse method, which is not shown in the drawings, is used. After the injection molded product of the band-shaped base material 8 which has been separately molded is incorporated into the cavity of the mold 16, the gut protective body 1 is molded by injection molding the synthetic resin material for molding the gut protective member into the gap. Such a method can also be taken.

As a material of the gut protection member 12 which forms the upper layer of the gut protection body 1, a synthetic resin material having excellent wear resistance and moderate flexibility is desirable. Specifically, amide resins such as nylon, olefin resins such as polypropylene and polyethylene, ABS,
Examples thereof include styrene resins such as AES, ester resins such as polycarbonate and polyethylene terephthalate, and ether resins such as polyacetal. Among them, the above materials have a flexural modulus of 5000 kg / cm ^{2 to} 15,000 k.
g / cm ² , and preferably 7 g / cm ^2.
Materials having characteristics of 000 kg / cm ^{2 to} 10,000 kg / cm ² are preferred. The material has a flexural modulus of 5000
If it is smaller than kg / cm ^2, it is difficult to use for a long time due to poor abrasion resistance.
In the cylindrical portion 9 of the tube 2, there is a possibility that the tube portion 9 may be easily damaged at a contact portion with the gut insertion hole 6. If the bending elastic modulus of the material is larger than 15000 kg / cm ² , the material lacks flexibility, and it is difficult to mount the gut protection member 12 along the shape of the outer peripheral surface 3 of the hitting portion 2. .

The material constituting the band-shaped base material 8 which forms the lower layer of the gut protection body 1 has good shape-retaining properties, excellent moldability (handling properties), and temperature from low to high temperatures. A soft synthetic resin material having a small difference in hardness due to the change is desirable. Examples of preferable materials include, for example, elastic materials or viscoelastic materials made of styrene-based elastomer, polyester elastomer, PVC-based elastomer, EVA, EPDM, thermoplastic polyurethane elastomer, polyethylene elastomer, polyamide elastomer, and the like. The flexural modulus of the material is 1000k
preferably a material having a characteristic of ^{g / cm 2 ~4000kg / cm 2} , more 1500kg / cm ² ~2500k
Materials having properties of g / cm ² are preferred. If the flexural modulus of the material is less than 1000 kg / cm ² , it is difficult to maintain shape retention and difficult to handle, and if the flexural modulus of the material is greater than 4000 kg / cm ² , The bulging portion 14 is unlikely to be deformed by an in-plane stress applied at the time of impact, and the striking surface cannot have sufficient elasticity.

As described above, in the gut protection body 1 of the present embodiment, as the configuration of the gut protection member 12 constituting the upper layer, an example in which the ear portions 11 are extended at both ends in the width direction of the band portion 10 has been described. However, the present invention is not limited to this. As shown in FIG. 6, a configuration without the ear 11 may be employed.

FIGS. 7 and 8 show another embodiment of the present invention. That is, the gut protection body shown in FIG. 7 shows the second embodiment of the present invention, and the basic configuration is the same as that of the above-described embodiment. , Beam 1 supporting left and right side walls 18 of bulging portion 14
9 is integrally formed. FIG.
Shows a third embodiment of the present invention, in which the width of the bulging portion 14 provided in the strip-shaped base material 8 and the width of the window hole 13 are increased, and the side wall 18 of the bulging portion 14 is provided with gut protection. Member 12
Is formed so as to be in contact with the rising portion of the ear 11.

According to the configuration of the second and third embodiments, it is possible to suppress the bulging portion 14 from moving in the width direction (the direction of the arrow) perpendicular to the in-plane direction, and only in the in-plane direction. Will be allowed to elastically deform.

[0032]

EXAMPLES In order to confirm the effects of the present invention, gut protectors of Example 1 described below and Comparative Examples 1 to 3 were prepared.

That is, as shown in FIGS. 1 to 3, the gut protection body prepared as Example 1 is formed into a band shape through the window hole 13 formed in the band portion 10 of the gut protection member 12 as in the above-described embodiment. One having a configuration in which the bulging portion 14 of the base material 8 was bulged was prepared. The gut protection member 12 is
The belt-shaped substrate 8 is formed of a nylon resin having a flexural modulus of 7800 kg / cm ² , and has a flexural modulus of 1800 kg.
/ Cm ² of nylon elastomer.

As Comparative Example 1, FIG.
As shown in FIG. 2B, a band-shaped body having a flat outer surface without forming a two-layer structure like the gut protection body 1 of the first embodiment was prepared. The gut protective body of Comparative Example 1 was formed of a nylon resin having a flexural modulus of 7,800 kg / cm ² .

As Comparative Example 2, FIG.
As shown in (a) and (b), the gut protection body of Comparative Example 1 was prepared by integrally forming a bulge 20 on the outer surface of the band portion 10. The same material as that of Comparative Example 1 was used to form the gut protective body of Comparative Example 2.

Further, in Comparative Example 3, as a material for forming the gut protective body, the flexural modulus was 1800 kg / cm.
A gut protector having substantially the same configuration as that of Comparative Example 2 except that the nylon elastomer ² was used was prepared.

The gut protection bodies of Example 1 and Comparative Examples 1 to 3 were mounted on a racket frame, and an actual hit test was performed. In this actual hit test, a ball was hit with a racket frame equipped with the gut protection bodies of Example 1 and Comparative Examples 1 to 3 for a general amateur player, and the hit felt by the player The resilience at the time, feeling (hit feeling), controllability and the like were evaluated. The test results at this time are shown in Table 1 below.

[0038]

[Table 1]

After the actual hitting test, the gut was removed from the racket frame, and the degree of damage to the gut protection body was also verified. The results at this time are shown in Table 2 below.

[0040]

[Table 2]

From the results of such tests and verifications, the gut protective body 1 of the first embodiment can obtain excellent durability as compared with the gut protective bodies of Comparative Examples 1 to 3, and at the same time, have a good It was confirmed that excellent effects were obtained in resilience, controllability, and shot feeling.

[0042]

As described above, the present invention provides a belt-like base made of a soft synthetic resin material provided with a large number of through-holes corresponding to the outer peripheral surface side openings of the gut insertion holes penetrating the inner and outer peripheral surfaces of the hitting portion. Gut protection comprising a material, a plurality of cylindrical portions superposed on the surface of the band-shaped base material, and inserted into respective through holes, and a gut protecting member including a band portion connecting the plurality of cylindrical portions. A body, wherein a window hole is formed in a band portion of the gut protection member where the gut is folded and stretched, and a soft bulging portion integrally formed from the window hole on the upper surface of the band-shaped base material. However, since it is configured so as to bulge out of the band portion through the window hole, the gut stress due to the gut stretching, the band-side opening region of each adjacent cylindrical portion, Since it is received and dispersed by the bulging part, gut is stretched with high tension or repeated Alternatively, no such also would Kitashi easily damaged by use.

Also, at the time of impact, the soft bulging portion that receives the gut outside the band portion is pressed in the in-plane direction by the stress applied at the time of the impact and is deformed, thereby temporarily loosening the gut. By imparting appropriate elasticity to the hitting surface, good resilience, controllability and a soft feel at impact can be exhibited.

Further, in the gut protection body of the present invention, when the gut protection member and the band-shaped base material are superimposed, the cylindrical portion provided on the gut protection member is inserted into the through hole of the band-shaped base material. Since the bulging portions provided on the upper surface of the band-shaped base material are configured to be fitted and engaged with each other in the window holes of the gut protection member, the connection between the two is strong and causes a gap. It can be combined accurately without any.

[Brief description of the drawings]

FIG. 1 is an external view of a gut protection body of the present embodiment.

FIG. 2 is an exploded view of the gut protection body of the present embodiment.

FIG. 3 is an enlarged end view of a main part along a line AA in FIG. 1;

FIG. 4 is an explanatory diagram illustrating a state in which a gut is stretched on the gut protection body of the present embodiment.

FIG. 5 is an explanatory view illustrating a method for manufacturing a gut protection body of the present embodiment.

FIG. 6 is an explanatory diagram showing another embodiment.

FIG. 7 is an explanatory diagram showing another embodiment.

FIG. 8 is an explanatory diagram showing another embodiment.

FIG. 9 is an explanatory diagram of a gut protection body of Comparative Example 1.

FIG. 10 is an explanatory view of a gut protection body of Comparative Example 2.

FIG. 11 is a front view of the racket frame.

FIG. 12 is an explanatory view of a configuration in an area a in FIG. 12;

FIG. 13 is an explanatory end view showing a state in which a gut is stretched on a conventional gut protection body.

FIG. 14 is an explanatory view of a conventional gut protection body.

FIG. 15 is an explanatory view of a conventional gut protection body.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 gut protective body 2 hitting portion 3 outer peripheral surface 4 gut protection groove 5 bottom wall 6 gut insertion hole 7 through hole 8 band-shaped base material 9 cylindrical portion 10 band portion 11 ear portion 12 gut protection member 13 window hole 14 bulging portion 15 gut Reference Signs List 16 mold 17 gap 18 side wall 19 beam 20 bulge 31 hitting part 32 grip part 33 shaft part 34 outer shell layer 35 outer peripheral surface 36 inner peripheral surface 37 gut insertion hole 38 gut protection groove 39 band part 40 cylinder part 41 gut protection body 42 Hole 43 gut 44 ball striking surface 45 stop 46 band 47 gut protective body 48 bulge

Claims (7)

[Claims] 1. A band-shaped base made of a soft synthetic resin material provided with a large number of through-holes corresponding to an outer-peripheral-surface-side opening of a gut insertion hole penetrating an inner / outer-peripheral surface of a hitting portion; A gut protection body comprising: a plurality of cylindrical portions that are polymerized and inserted into respective through-holes; and a gut protection member including a band portion that connects the plurality of cylindrical portions, wherein the band-shaped base material is provided. Characterized in that at least a part of the gut protector bulges through a window formed in a band portion of the gut protector. 2. The gut protection body according to claim 1, wherein the window hole is formed at a portion where the gut between the adjacent tubular portions is folded and stretched. 3. The swelling portion to be inserted into the window hole is integrally formed on the surface of the strip-shaped base material corresponding to the window hole. Got protection. 4. The gut protection body according to claim 3, wherein the bulge is a bulge that penetrates through the window and is exposed to the outside. 5. The gut protection body according to claim 4, wherein the bulging portion is formed in an arc shape straddling an arch between adjacent tubular portions. 6. The gut protection member has a flexural modulus of 5
2. A material made of a relatively hard material of 000 kg / cm ^{2 to} 15000 kg / cm ^2.
The gut protective body as described. 7. The belt-shaped substrate has a flexural modulus of 1000.
kg / cm ² ~4000kg / cm is formed from ^two of the relatively soft material, characterized in that has claim 1 gut protection body according.