JPH03501336A - Ball striking devices, especially tennis or squash rackets - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Ball striking device 1 The present invention relates to a ball striking device, in particular, a shaft including a hand grip and a head coupled to the shaft; Concerning tennis or squash rackets. The frame of the head is especially The net extends approximately parallel to the longitudinal axis of the shaft. formed by warp threads extending across the shaft and transverse threads extending transversely to the longitudinal axis of the shaft; These threads are made of plastic, gutt or similar materials. .

Such ball striking devices are generally well known and therefore need not be described in detail. There is no.

To maintain the health or vitality of the user, i.e. the tennis or squash player. In order to effectively suppress vibrations, that is, to reduce vibrations, one more thing must be done. constitutes a problem: At this point, there is no separate Additional devices of greater or lesser complexity have been used, such as synthesizing shock absorbers. . A shock absorber installed on the net absorbs vibrations caused by placing the net directly on the net. It is also known that this decreases due to However, in all cases additional concerning structural measures of the United States, which require corresponding efforts and which are limited. It only shows the effect of

Therefore, the object of the invention is that by its basic structure, i.e. without any additional measures. In addition to reducing vibration, it also provides protection against slices and top spin. Obtaining an enlarged sweet spot with unique advantages due to the design It is an object of the present invention to provide a ball striking device of the above-mentioned type that can perform the following operations.

According to the invention, this object can be achieved in the simplest manner according to the characteristic requirements of claim 1. resolved by law.

The present invention provides that a tennis racket can be compared to a tuning fork, i.e., a normal tennis racket. The observation that a racket can be compared to a symmetrical tuning fork whose fork parts vibrate equally Based on. These vibrations are completely transmitted through the shaft during tennis or skateboarding. It is conveyed to the arm of the player of the game.

The tennis or squash racket according to the invention has - reduced vibrations; The fork can be compared to a tuning fork that vibrates differently, thereby reducing vibrations. No additional measures are needed to reduce the does not require any additional effort during the process and is therefore in fact extremely simple and effective That is clear.

Furthermore, the design according to the invention has a so-called sweet spot with a maximum length in the longitudinal direction. In the area of the thread it is further extended and expanded accordingly, thereby increasing the play of the racket. This has the advantage that the play performance is improved accordingly. This advantage lies in the so-called slide Specially given to strokes and top strokes. These types of straws If the net is struck in the elastic area, then rolls along the net, and the increased pressure It leaves the net again in the region of the shorter curling yarn acting on the ball.

Preferably, the transverse offset of the longest longitudinal thread is between two adjacent ones in the center of the net. corresponds at least approximately to the distance between the machine direction threads. Tests have shown that lateral offset The cut or deviation is twice the distance between two adjacent longitudinal threads in the center of the net. It has been shown that it is advantageous to correspond to three times the

Hereinafter, embodiments of the tennis racket of the present invention will be described in detail with reference to the accompanying drawings. Ru. In the accompanying drawings, FIG. 1 is a plan view of a tennis racket according to the present invention. ri, and Figure 2 shows the impact on the ball from impact point A until the ball leaves the net again. Comparing the pressure of the conventional tennis racket and the tennis racket of the present invention. FIG.

The tennis racket 10 shown in the plan view of FIG. 1 has a hand grip 11. a shaft 12 and a head coupled to the shaft 12; The beam 16 defines a striking surface or net 15, the net extending longitudinally of the shaft. warp yarns 22 extending substantially parallel to the longitudinal axis 19 and transverse to the longitudinal axis of the shaft; It is formed by extending transverse threads 23, these threads are made of plastic, guttate or It is made with something equivalent to these. Between head frame 16 and shaft 12 The transition part is formed by a so-called open heart. In this respect, A tennis racket with a frame made of metal, wood and/or plastic. Compatible with regular tennis rackets.

To reduce vibrations, the head frame 16 is aligned with the longitudinal shaft axis 19. It is asymmetrical. Specifically, the head frame has different lengths. Contains two frame branches or frame branches 27.28, which include Therefore, the longest thread 20 in the longitudinal direction is off in the transverse direction with respect to the longitudinal shaft axis 19. Set or off. In the example shown, the longest yarn in the machine direction 2 A transverse deviation of 0 is the difference between two adjacent longitudinal threads 2 in the central part of the net 15. This corresponds to approximately 2.5 times the distance between the two.

Furthermore, the two frame branches 27, 28 have different stiffness and elasticity. 0 Normal symmetrical head frame 16 design reduces vibrations Providing two frame branches 27, 28 with different stiffness for Both are basically conceivable.

However, this is the sweet subotsu) (sweet 5) already mentioned above. Enlargement of the sweet spot that does not result in enlargement or elongation of the sweet spot In FIG. There is.

Of course, the head frame 16 according to the illustrated embodiment is of a conventional manner of monolithic design. In the illustrated embodiment, the shaft 12 is integrally connected to the shaft 12. The different lengths of the two frame branches 27, 28 mean that the heart web 14 The heart extends at an angle to the longitudinal shaft axis instead of extending across the axis. - Obtained by designing or arranging the web 14.

The same effect can be achieved by maintaining the normal alignment of the heart web 14 while maintaining the longitudinal shaft. Near the axis 19, the left or right frame branch 27 or 28 is moved outwardly or by bending it inward and lengthening or shortening it accordingly. can be achieved.

For pure vibration damping, two frames are installed at approximately half the height of the head frame 16. It is basically conceivable to bend one side of the arm branch inward or outward. , whereby said branch is correspondingly shortened or lengthened. . The transverse size of the sweet spot can then be changed as well, with the racket Corresponding effects can be achieved during the game.

However, the embodiment shown in FIG. , in that the basic shape of the tennis racket remains substantially unchanged. and is itself distinct. The only change is that the heart - the web 14 is inclined and correspondingly the longest longitudinal thread 20 is geometrically longitudinal This means that the shaft axis 19 of Therefore, sweet The spot is extended downward in the region of the longest longitudinal threads 20 (region 18 ), as opposed to the ideal case of slice or top spin, this is Impact point A of the ball 21, the tennis ball is on the further path of the slice. Next, cross the net in the direction of arrow 24, that is, approximately parallel to the transverse thread 23. It rolls and leaves the net at point B. In this way, the ball 21 has maximum elasticity Strike the net in the zone, where it is virtually embedded in the net and gives the necessary spin. available.

During the rolling of the ball 21 in the direction of the arrow 24, the pressure P acting on the ball is: It gradually increases according to curve 25 in FIG. The increase in pressure is in the direction of arrow 24. This can be attributed to the longitudinal threads 22 becoming increasingly shorter.

In a normal tennis racket, the largest longitudinal thread is the geometric longitudinal shaft axis 1 9, i.e. in the center, which means that from A to B of ball 21 The result is that during rolling, a pressure characteristic occurs that corresponds to curve 26 in FIG. Ru. Therefore, Figure 2 shows the 1 illustrates additional advantages of the tennis racket shown in FIG.

Thus, during its natural vibration, the tennis racket shown is “out of tune.” ”, thereby achieving high vibration reduction. With heart web 14 The vibration of the left head frame branch 28 is caused by the vibration of the left head frame branch 28. This is a total vibration that is superimposed on the vibration of branch 27 and is thereby significantly reduced. The injury acts on the shaft 12. Here, the total vibration is 28 on the one hand and 28 on the other hand. almost completely reduced by the magnitude of the correspondence of the two frame branches of 27 obtain.

In the example shown, the two head frame branches 27, 28 have different Thus, the left head frame branch 28 in FIG. This is due to the fact that it additionally comprises a root web 14. heart u The left frame branch 28 containing the web 14 is the same as the right frame branch. 27 to the right. Therefore, in Figure 1, net 15 The longitudinal axis of symmetry is also shifted to the right with respect to the geometrical longitudinal shaft axis 19. Ru. It is placed approximately in the area of the largest machine direction thread 20.

All features disclosed herein, whether individually or in combination, are The invention is required to be essential to the invention to the extent that it is novel to the art. Ru.

Submission of translation of written amendment (Article 184-8 of the Patent Law) March 19, 1990

Claims (1)

[Claims] 1. a shaft (12) including a hand grip and coupled to the shaft (12); The frame (16) of said shaft has a striking surface, in particular a net. (15), the net extending approximately parallel to the longitudinal shaft axis (19). a warp thread (22) extending transversely to said longitudinal shaft axis; and a transverse thread (23) extending transversely to said longitudinal shaft axis. These threads are made of plastic, gut or similar material. A ball striking device, especially a tennis or squash racket, made by In, With respect to the longitudinal shaft axis (19), the head frame (16) Two frame blocks each of different length and/or different stiffness or elasticity with launches (27, 28), and the different lengths result in a maximum length of machine direction thread ( 20) is shifted laterally (offset) with respect to the longitudinal shaft axis (19). A ball-striking device, especially for tennis or squash. racket. 2. The horizontal deviation of the maximum length of the longitudinal thread (20) is determined by the position of the center of the net (15). corresponds at least approximately to the distance between two adjacent machine direction threads (22) at A ball striking device according to claim 1, characterized in that: