JPH02203878A - Racket - Google Patents

Abstract

PURPOSE: To improve cushioning performance of a racket incorporating air cushion of elastomer expanded with a specific air pressure between inner frame and outer frame. CONSTITUTION: The elastomer is composed of several pieces of elastic units fixed between the inner and outer frames along their circumference, and a solid body or enclosed hollow structure, for instance, an expanded air cushion. The air pressure in the expanded air cushion is from 0.5kg/cm<2> to 6kg/cm<2> (gauge), and the working air pressure in the expandable air cushion is preferably in the range between 0.3kg/cm<2> and 8kg/cm<2> . The elastomer is formed into a freely expandable ring-form seamless endless air strap 105. This air strap is to be rubber-made. An air valve 104 working as an air expansion unit is placed on the air strap. The air valve 104 of the air strap 105 is fixed by inserting into a small hole on the outer frame 101, and the air strap 105 is put into a groove around the outer frame 101, then the inner frame 102 equipped with stretched strings 103 is fixed with the air strap 105 to assemble the outer frame 101.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a new type of racket, particularly a tennis racket, which allows shock absorption.

[Background Art] In recent years, tennis has become popular in all countries of the world and has become a national sport in many countries. However, the problem of buffering tennis rackets has not yet been satisfactorily solved. Many (
of tennis fans are suffering from tennis overwork disease and tennis elbow. This is due to the racket's poor cushioning performance, which hinders players' work, study, and life. The materials used for tennis rackets are aluminum-based alloys, glass fiber: graphite, or graphite.

Wooden rackets are inexpensive, but have low strength and poor cushioning performance. Fiberglass or graphite rackets are strong but expensive. Numerous efforts have been made to provide rackets with better cushioning performance. Although some new cushioning equipment or new cushioning materials have been introduced by manufacturers to increase the cushioning capacity, neither of them are satisfactory for the sport of tennis.

[Problem to be solved by the invention]

An object of the present invention is to provide a new racket with improved cushioning performance.

[Means and actions to solve the problem]

The racket according to the invention consists of an inner frame on which the strings are tensioned, an outer frame integral with the handle, and a piece of elastomer assembled between the inner frame and the outer frame. kg /
Air cushions inflated with air pressures ranging from cnN to 6 kg/c+fl (gauge) or enclosed inflatable air cushions with an air inflation device on top, with operating air pressures preferably from 0,3 kg/cIII The one with 8 kg/cd (gauge) is good.

The elastomer biases the two frames and provides a non-rigid connection between the two frames. Cushioning performance is provided by this elastomer.

The elastomer is preferably a variety of materials having appropriate strength, elasticity, flexibility, and airtightness, such as rubber, plastic, or polymeric synthetic materials. The elastomer is, for example,
It may consist of a monolithic piece of various shapes, such as an endless annular shape, or several pieces of elastic units fixed between them along the periphery of the two frames. The elastomer may be a solid body or an enclosed hollow structure, such as an inflatable or inflatable air cushion. Good cushioning performance is obtained by maintaining air pressure within the air cushion. The air pressure range for obtaining good cushioning performance within the air cushion varies depending on various factors, primarily the size of the air cushion or the shape of that portion of both frames. The air pressure in the inflatable air cushion is as above < 0.5 kg/cfiY to 6 kg/c+fi (gauge), and the operating air pressure in the inflatable air cushion is 0.3 kg/cd to 8 kg.
/cT11 is preferred.

The inflatable air cushion may include an air inflation device to inflate the air cushion and maintain air pressure therein. The air expansion device may be any of the various expansion devices known in the art, such as an air valve. The air cushion may have a single layer structure or a double layer structure consisting of an inner layer and an outer layer.

The single layer air cushion may be in the form of an air strap, with this inner layer maintaining air pressure inside.

The inner and outer frames can be manufactured by conventional methods in the same manner as conventional rackets using various materials such as fiberglass, graphite, aluminum-based alloys, wood, etc. One or more circumferential grooves may be formed on the outer circumference of the inner frame and/or on the inner circumference of the outer frame for accommodating the corresponding elastomer. The section of this groove is formed, for example, in a semicircular recess. If an inflatable air cushion is used as the elastomer, at least one passage hole is provided in the outer frame through which the air inflation device can pass.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

In FIGS. 1 to 4, the outer frame (101) and the inner frame (102) are made of glass fiber, graphite, or the like. An annular groove (106) communicating with each other is provided on both frames. The harmonious section was semicircular. The elastomer was in the form of an inflatable annular seamless endless air strap (105). This air strut was made of rubber. An air valve (104) was provided on the air strap to act as an air expansion device. [(10B) is the racket handle].

In this embodiment, the air valve (104) of the air strap (105) is inserted into the small hole on the outer frame (101) and fixed, and then the air strap (105) is inserted into the circumferential groove on the outer frame (101). (see Figure 1) and then the inner frame (102) with stretched strings (103) (see Figure 2) is secured with air straps (105) to the outer frame (101). assembled. [(107) is a hole for string, (
106) is the groove of the air strap. ] The method of assembling the air straps (105) to the inner frame and the outer frame is similar to that of wheel tires and wheel rims (see FIGS. 3 and 4). Finally, fill the air strap (105) with the required amount of air via the air valve and adjust the air pressure from 0.3 kg/cTIt to 8.
The range was kg/cIIY (gauge).

The air strap (105) sufficiently filled with air is energized to separate the outer frame (101) and the inner frame (102).
The inner frame (102) and the outer nuclear frame (
101) were integrally combined. If you hit the ball with this racket, Paul will impact the string (103).

The racket according to the present invention forms a cushioning cushion with the air strap (105) to greatly absorb the shock impact. Therefore, the shock removal effect is achieved to the maximum extent.

Figures 5 and 6 illustrate a second embodiment of the invention.

The difference between the second embodiment and the first embodiment is the outer frame (201
) and the inner frame (202) are made of an aluminum base alloy, and the inflatable air strap (205) is
The point is that the butyl rubber of the VA (polyvinyl alcohol) film is formed with a pvoc <polyvinylidene chloride) film and a synthetic film coated with cotton. [(208) indicates the handle of the racket. [Effects of the Invention] The racket of the present invention having the above structure has a satisfactory buffering performance compared to conventional rackets, thereby effectively preventing specific muscle fatigue and diseases such as tennis elbow.

[Brief explanation of the drawing]

Fig. 1 is a front view of the outer frame with the air strap fixed to it, Fig. 2 is a front view of the inner frame with the strings stretched, Fig. 3 is a front view of the racket showing the first embodiment of the present invention, and Fig. 4 is a front view of the inner frame with the strings stretched. 3 is a sectional view taken along line I-1 in FIG. 3, FIG. 5 is a front view of a racket showing a second embodiment of the present invention, and FIG. 6 is a sectional view taken along line ■-■ in FIG. 101...Outer frame, 102...Inner frame, 103...String, 104...Air valve, 105...Air strap, 106...Groove, 107...Hole (for string).

Claims (1)

[Claims] 1. A racket comprising an inner frame stretched by a string, an outer frame integrally formed with a handle, and at least one elastomer assembled between the inner frame and the outer frame. . 2. The racket of claim 1, wherein the elastomer is an expanded air cushion. 3. The racquet of claim 1, wherein said elastomer is an enclosed inflatable air cushion with an air expansion device. 4. The air pressure inside the expanded air cushion is 0.5k.
3. The racket according to claim 2, having a weight in the range of g/cm^2 to 6 kg/cm^2 (gauge). 5. The air pressure during operation inside the inflatable air cushion is 0.3 kg/cm^2 to 8 kg/cm^2 (gauge)
4. The racket according to claim 3, wherein the racket is in the range of . 6. The racket according to claim 2 or 3, wherein the air cushion is endless. 7. The air cushion has a single layer seamless structure;
The racket according to claim 2 or 3. 8. The racket according to claim 2 or 3, wherein the air cushion has a two-layer structure. 9. The racket according to claim 2 or 3, wherein the air cushion is made of rubber. 10. The racket of claim 2 or 3, wherein the air cushion is an endless air strap. 11. The racket of claim 3, wherein said outer frame has at least one passage hole through which said air expansion device can pass. 12. The racquet of claim 1, wherein the outer frame has interrelated peripheral grooves along an inner periphery of the outer frame. 13. The racket of claim 1, wherein said outer frame has grooves spaced along an inner circumference of said frame. 14. The racquet of claim 1, wherein the inner frame has interrelated peripheral grooves along the outer periphery of the inner frame. 15. The racket of claim 1, wherein the inner frame has grooves spaced apart along the outer circumference of the inner frame. 16. Claims 12 to 1, wherein the groove section has a concave shape.
Any one of 5 rackets. 17. The racket of claim 16, wherein the groove section is semicircular.