JPH0430867A - Gut for packet - Google Patents

Abstract

PURPOSE:To make vibrations of a gut surface absorb in hitting a ball for preventing tenniselbow by using elastic fibers for at least a part of filament fibers of a plurality of filament fibers. CONSTITUTION:A gut 1 consist of a plurality of synthetic resin filament fibers 2 and elastic fibers 3 are used for a part of a plurality of the filament fibers, or the gut 1 consists of core component fibers 4 of filaments and cover component fibers 5 of filaments wound around the outer peripheral surface of the core component. In either case, a sheath part is formed of nylon filaments and a part of the fibers is made of elastic filaments 3 so that the core component fibers 4 and cover component fibers 5 may be fixed by adhesives 6. Preferably the elastic fibers are polyurethane fibers, polyester-polyether copolymer fibers and polyamide-polyether copolymer fibers.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a string for a racket, and more specifically to a string made of synthetic resin and used for being attached to a racket, which is a hitting tool for tennis, badminton, etc. Regarding Guttu, which has excellent impact resistance.

[Prior Art] The functions required of rackets, which are ball hitting equipment for tennis, badminton, etc., include physical properties such as strength, durability, light weight, and impact when hitting the ball, and various properties such as fashionability. is required. In order to substantially satisfy these requirements, it has become mainstream in the industry to manufacture racket frames from fiber reinforced resin (FRP) such as carbon fiber, glass fiber, or ceramic fiber. As another material, frames made of lightweight alloys such as aluminum alloys are also known.

Racquet frames made of FRP or lightweight alloys are lighter and more rigid than conventional racket frames made of wood or bamboo (and are now widely used by everyone from beginners to top professionals).

However, as the above-mentioned highly rigid rackets become popular, the occurrence of so-called tennis elbow, which causes damage to the elbows and arms, has become a problem.

This is due to the high rigidity of the racket frame.
This seems to be due to the fact that the vibration caused by the impact when hitting the ball cannot be damped quickly.

As a proposal for mitigating the impact when hitting a ball, it is proposed to use a hollow head structure and a vibration damper (Japanese Patent Publication No. 52-134).
No. 55), grip material with good vibration absorption, grip structure, and yoke member (Japanese Patent Laid-Open No. 61-203
It is also known to use a string-like body with high vibration absorption properties on the gut surface (Japanese Unexamined Patent Publication No. 150082/1982), and to sandwich rubber, foam resin, etc. on the gut surface.

[Problems to be Solved by the Invention] However, although each of the above-mentioned conventional techniques has some effects, there is a problem in that the effects are not sufficient. In other words, the use of a vibration damper or the method of sandwiching rubber or foam resin between the gut surfaces can absorb the impact of some of the guts that are in contact, but the problem is that they are less effective against guts that are not in contact. be.

Furthermore, the use of string-like bodies poses a problem of appearance. Additionally, structural improvements such as frames and grips pose a problem in that they place restrictions on the shape of the racket.

SUMMARY OF THE INVENTION In order to solve the problems of the prior art described above, an object of the present invention is to provide a racket string that can sufficiently absorb large vibrations generated in the racket by imparting shock-reducing properties to the string itself. .

[Means for Solving the Problems] In order to achieve the above object, the racket string of the present invention is a racket string made of a plurality of filament fibers made of synthetic resin, wherein at least one of the plurality of filament fibers is It is characterized in that some of the filament fibers are elastic fibers.

Further, the racket string of the present invention is a racket string having a core-sheath structure comprising at least a core component made of filament fibers and a covering component made of filament fibers wound around the outer peripheral surface of the core component. The core component fiber and the covering component fiber both contain nylon filament fibers, and at least some of the fibers constituting the sheath portion are elastic fibers.

In the above, the elastic fibers include polyurethane fibers, polyester-polyether copolymer fibers, and polyamide-based fibers.
It is preferable to use at least one type of fiber selected from polyether copolymer fibers.

[Function] According to the configuration of the present invention, since elastic fibers are used for at least some of the plurality of filament fibers, the rubber elasticity of the elastic fibers causes a large amount of damage that occurs on the stiff surface at the moment of hitting the ball. Vibration can be sufficiently absorbed by the gut surface.

According to another configuration of the present invention, both the core component fiber and the covering component fiber contain nylon filament fibers, and at least some of the fibers constituting the sheath portion are made of elastic fibers, so that the nylon filament fibers provide strength and rigidity. At least a portion of the elastic fibers constituting the sheath portion can sufficiently absorb the large vibrations generated on the gut surface at the moment of hitting the ball.

Further, according to the preferred configuration of the present invention, since at least one type of fiber selected from polyurethane fibers, polyester-polyether copolymer fibers, and polyamide polyether copolymer fibers is used as the elastic fiber, the elastic fibers are more durable. It can be made to have excellent impact mitigation properties and also excellent durability.

[Example] The present invention will be explained in more detail below using Examples.

FIGS. 1 to 4 are model illustrations of cross-sectional examples of gutts 1 according to embodiments of the present invention.

In FIG. 1, a gut 1 is made up of a plurality of filament fibers 2 made of synthetic resin, and at least some of the filament fibers have elastic fibers 3.
It uses 6 is an adhesive layer.

FIG. 2 shows core component fibers 4 made of filament fibers,
The core component fibers 4 and the covering component fibers 5 are both made of nylon filament fibers, and at least a portion of the sheath portion is made of filament fibers and is wound around the outer peripheral surface of the core component. A string 1 whose fibers are elastic filament fibers 3 is shown. and,
The core component fiber 4 and the covering component fiber 5 may be fixed by an adhesive layer 6. Moreover, although FIG. 2 illustrates monofilament as the core component fiber, multifilament may also be used.

Even the cross-sectional shapes shown in FIGS. 1 and 2 can be used as a practical racket gut.

FIG. 3 shows a gut 1 having a structure further including a coating layer 7 around the coating component fibers 5 of FIG.

FIG. 4 is a cutaway perspective view of FIG. 3.

In the above, the outer diameter of the gut 1 is 0.5 to 2.0 m.
It is preferable that it is about m. The fibers 2 and core component fibers 4 preferably have a denier of about 1,000 to 20,000 denier, and the coated component fibers 5 preferably have a denier of about 30 to 1,000 denier.

The elastic fiber 3 is also preferably about 30 to 1000 denier.

Denyl here refers to the weight (duram) per 9000 m of fiber length.

In FIGS. 1 to 4, two elastic fibers 3 are shown, one single fiber in total, but it is of course possible to have two or more.
A plurality of elastic fibers may be present next to each other.

Furthermore, the filament fibers 2 made of synthetic resin, the core component fibers 4 made of filament fibers, and the covering component fibers 5 made of filament fibers are made of polyamide (for example, nylon 6.6.6
Highly rigid filament fibers such as nylon, polyester (polybutylene terephthalate, polyethylene terephthalate, etc.), polyolefin, polyphenylene sulfide (PPS), polyetheretherketone (PEEK), etc. are used. Particularly preferred fibers are nylon 6 and 6,6 nylon.

Furthermore, as the elastic fiber 3, it is possible to use what is generally called a thermoplastic elastomer, such as polyurethane fibers, polyester-polyether copolymer fibers, polyamide-polyether copolymer fibers, and other synthetic rubbers. can be used. Among these, the elastic fibers are preferably selected from polyurethane fibers, polyester-polyether copolymer fibers, and polyamide-polyether copolymer fibers. This is because it has excellent impact relaxation resistance and also excellent durability.

In the above, 1. Polyurethane fibers are fibers having urethane bonds that are polymerized from diisocyanates and polyols, and are commonly known as spandex. That is, diisocyanates such as tolylene diisocyanate and 1,5-naphthalene diisocyanate,
It is polymerized from polyols such as ethylene oxide, propylene oxide, butylene oxide, or polyester type polyols (also referred to as polyhydroxy compounds).

Further, as the polyester-polyether copolymer fiber, for example, a copolymer consisting of polybutylene terephthalate and poly(1,4-butanediol) [or poly(tetrahydrofuran)] can be used. In this product, the polyester component becomes the hard segment, and the polyether component becomes the hard segment. Known product names include "Hytrel" manufactured by DuPont Azuma.

Polyamide-polyether copolymer fibers include, for example, block copolymers comprising hard segments of nylon 11.12 or 6 and soft segments of polyether.

Known product names include "Crylax A" and "Crylax E" manufactured by Dainippon Ink and Chemicals.

It is preferable that the elastic fiber 3 has a rubber elastic modulus of 200% or more. Here, the elastic modulus is [(A'l
-I! o) /A'o]X100 (%), where / represents the length of the elastic fiber at the time of initial load in a substantially unstretched state, and 11 represents the length at break.

It is preferable that the strings 1 are usually twisted.

This will be explained in more detail below using experimental examples.

Measurement method In the following examples, the vibration damping properties of guts were measured as follows.

Stretch 1 meter of guttah with a tension of 60 pounds, attach a sensor 2 cm from the edge, and attach an 800 pound to the center point.
A load of g is applied to the specimen, and the time required for the vibration to stop completely is evaluated.

Example 1 A nylon 6 monofilament with a diameter of 1.0 mm was used as the core component fiber, and a diameter of 0.16 mm was used as the cover component fiber.
19 pieces of nylon 6 and two pieces of 560 denier polyurethane (Opelon, manufactured by DuPont East) were wound in a helical shape (200 times/m) and fixed at the same time using a nylon adhesive. This product has a cross-sectional view shown in Figure 2, has a strong cuff of 6.7 kg, an elongation of 2363%, and a knot strength of 49.
It was a string-like body with a brightness of 8 dazzles and a diameter of 1.313 mm.

This surface was then coated with hot melt nylon 6. The guts obtained were as shown in FIGS. 3 and 4. The strength of this gut is 80.9kg, and the elongation is 2.
1.3%, nodule strength 48.4kg.

The diameter was 1.328 mm.

The vibration damping property of this gut was 4.4 seconds.

This gut is actually made of carbon fiber reinforced resin (CFRP)
When I tried it on a manufactured racket, I found that it had a mild feel at impact, and I could barely feel the impact when I hit the ball.

The feel of the ball at impact was similar to that of a wooden racket.

In contrast, the vibration damping properties of commercially available nylon guts are approximately 7.
It takes about a second, and the impact when hitting the ball is great.

Example 2 Nylon 6 monofilament with a diameter of 1.0 mm was used as the core component fiber, and a diameter of 0.16 mm was used as the cover component fiber.
17 pieces of nylon 6 and four pieces of 560 denier polyurethane (Opelon, manufactured by DuPont East) were wound in a helical shape (200 times/m) and fixed at the same time using a nylon adhesive.

This surface was then coated using a phenolic solution of nylon 6. The guts obtained were as shown in FIGS. 3 and 4. The strength of this gut is 83.0kg
, elongation 29.7%, knot strength 41.3kg, diameter 1.3
It was 30mm.

The vibration damping property of this gut was 2.1 seconds.

This gut is actually made of carbon fiber reinforced resin (CFRP)
When I tried it on a manufactured racket, I found that it had a mild feel at impact, and I could barely feel the impact when I hit the ball.

The feel of the ball at impact was similar to that of a wooden racket.

[Effects of the Invention] As explained above, according to the present invention, elastic fibers are used for at least some of the plurality of filament fibers. Large vibrations generated on the surface can be effectively absorbed by the firm surface. This prevents impact from being transmitted to the elbows and arms, thereby preventing the occurrence of so-called tennis energy.

According to another configuration of the present invention, both the core component fiber and the covering component fiber contain nylon filament fibers, and at least some of the fibers constituting the sheath portion are made of elastic fibers, so that the nylon filament fibers provide strength and rigidity. , and the large vibrations generated on the gut surface at the moment of hitting the ball can be efficiently absorbed by at least some of the elastic fibers constituting the sheath.

Further, according to a preferred configuration of the present invention, as the elastic fiber,
Since at least one type of fiber selected from polyurethane fibers, polyester-bodiether copolymer fibers, and polyamide-polyether copolymer fibers is used, it has excellent impact relaxation resistance and durability. can be taken as a thing.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a gut according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of a gut according to another embodiment of the present invention, and FIG. 3 is a cross-sectional view of a gut according to another embodiment of the present invention. FIG. 4 is a partially cutaway perspective view of FIG. 3. 1...Gut 2...Multiple synthetic resin filament fibers 3...
Elastic fiber 4...Core component fiber 5 consisting of filament fiber...
Covering component fibers made of filament fibers 6... Adhesive layer 7... Covering layer Patent applicant Gosen Iccho Co., Ltd.] Figure 1 Figure 2 Figure 4

Claims (3)

[Claims] (1) A racket string comprising a plurality of synthetic resin filament fibers, wherein at least some of the plurality of filament fibers are elastic fibers. (2) A racket string having a core-sheath structure comprising at least a core component made of filament fibers and a covering component made of filament fibers and wound around the outer peripheral surface of the core component, wherein the core component fibers and A string for a racket, wherein the covering component fibers both include nylon filament fibers, and at least some of the fibers constituting the sheath portion are elastic fibers. (3) Elastic fibers are polyurethane fibers and polyester.
The racket string according to claim 1 or 2, which is at least one type of fiber selected from polyether copolymer fibers and polyamide-polyether copolymer fibers.