EP1097730A1 - Racket for ball games - Google Patents

Abstract

The racquet or bat (30) has a hitting-head , a handle part between which is a frame possessing a heart-shaped piece (34).. The profiled part forming the frame has varying cross-sectional shapes corresponding to the main types of stress occurring. The frame has at least two bump-shaped reinforcement elements (51,53).

Description

The present invention relates to a sports racket or a racket for Ball games, especially a tennis racket with a tenter or Racket head to hold the covering, one on the stenter subsequent heart area and a handle or handle section.

In general, the energy of a player during the game forces on the covering of the The ball strikes the striker from its longitudinal axis. this leads to to a deterioration in accuracy when the ball is off the racket bounces off. Consequently, such a deflection of the tenter is for the direction of a played ball with responsibility. You can use the entire length of a field deviations of up to one meter from the desired Airline of the ball occur. The precision of known tennis rackets leaves thus much to be desired.

DE-A-34 34 956 and US-A-4 664 380 propose a racket in which the resonance frequency of the strung racket attached to the handle corresponds approximately to the length of time in which the ball with the covering is in contact. Here, the natural frequency of the racket with the Excitation frequency of the ball essentially match. As special favorable form for the racket is considered if the racket is in has the greatest height in its heart zone and extends to the handle as well also tapered towards the club head, i.e. in both directions of the longitudinal axis, preferably the greatest height in either side of the heart zone extending area is constant. The cross section of the stenter forming profile bar is essentially rectangular with changing height.

DE-A-39 10 871 shows a racket for ball games with a hollow tubular frame that forms a head, neck and shaft and carries a handle. The frame has a perpendicular to the fabric plane Direction a cross-sectional height that goes from the bottom of the neck to the end of the head increases uniformly, so that the rigidity of the frame with increasing distance from the handle grows. This arrangement where the frame is most flexible at the top of the handle, is supposed to decrease the angle to which the covering level is and should be deflected when hitting a ball have a shock-absorbing effect.

US-A-5 810 683 describes a sports racket, particularly one Tennis racket, with a changing around the circumference of the stenter Cross-sectional shape. The one that extends from the tip of the club head major part of the circumference of the stenter has an aerodynamic, i.e. a substantially oval cross-section. Which is from the handle section extending part of the frame has a rectangular cross-sectional profile, wherein the two profiles on each side through a transition section are fluidly connected to each other. The transition section between the Both cross-sectional profiles are located near the heart area and extends in a range of at most 15% of the total racket length.

While some of the rackets known in the art are relatively stiff are formed and thereby a deformation of the racket during the Reduce play, these rackets have the disadvantage that the improved Stiffness is achieved at the expense of increased weight. The higher weight however again worsens the handling of the racket during of playing and can lead to pain in the blow arm (tennis arm). Accordingly, with the rackets known from the prior art the optimal rigidity with low weight of the racket far from being met, so these well-known rackets continue to be desired leave.

The present invention is based on the object improved racket, especially an improved tennis racket to provide low weight with high rigidity. This object is achieved with the features of the claims.

The invention is based on the basic idea, depending on the stresses occurring in the respective frame position of the racket, such as e.g. Bending and torsion for the relevant type of stress provide optimal frame cross-sectional profiles. For example, it has demonstrated that a suitable cross-sectional shape for torsional stresses the frame profile is a circular cross-section while for bending stresses for example a substantially rectangular cross-sectional profile for the Racket frame is suitable.

By adapting the cross-sectional profile to the The respective frame position in the racket head reaches the invention Racket with low weight, e.g. less than 200g for one Tennis racket, optimal strength and manageability. Furthermore, it is preferred, also in the heart area or in the shaft area of the invention Racket a cross-sectional shape optimally adapted to the type of stress the frame profile at the respective position. This allows the Manageability and the playing properties of the racket according to the invention be further increased.

In addition, it may be preferable to narrow the racket at the head end, i.e. to train with a lower overall height. In particular, it is preferred to To provide racket at least one hump-like stiffening element that locally occurring loads can be absorbed. Corresponding a particularly preferred embodiment are in the heart area of the Two such bump-like stiffening elements are provided on each side of the racket, to provide a particularly stiff and light racket.

Fig. 1

eine Vorderansicht eines herkömmlichen Tennisschlägers gemäß Stand der Technik;

Fig. 2

eine Seitenansicht des herkömmlichen Tennisschlägers gemäß Fig. 1;

Fig. 3

eine Teilvorderansicht einer Hälfte einer bevorzugten Ausführungsform des erfindungsgemäßen Schlägers;

Fig. 4a bis 4t

Schnittdarstellungen verschiedener Querschnittsprofile entlang der in Fig. 3 eingezeichneten Schnittlinien;

Fig. 5

eine vergrößerte Teil-Vorderansicht einer Hälfte einer bevorzugten Ausführungsform des erfindungsgemäßen Schlägers, ähnlich Figur 3, wobei die Achsverhältnisse der Querschnittsprofile an den jeweiligen Schnittstellen angegeben sind;

Fig. 6

eine schematische Vorderansicht einer vereinfachten Ausführungsform des erfindungsgemäßen Schlägers;

Fig. 7

eine Schnittdarstellung des Querschnittsprofils entlang der Linie VII-VII von Fig. 6;

Fig. 8

eine Schnittdarstellung des Querschnittsprofils entlang der Linie VIII-VIII von Fig. 6;

Fig. 9

eine Schnittdarstellung des Querschnittsprofils entlang der Linie IX-IX von Fig. 6;

Fig. 10

eine Schnittdarstellung des Querschnittsprofils entlang der Linie X-X von Fig. 6;

Fig. 11

eine Schnittdarstellung des Querschnittsprofils entlang der Linie XI-XI von Fig. 6;

Fig. 12

eine Schnittdarstellung des Querschnittsprofils entlang der Linie XII-XII von Fig. 6.

The racket according to the invention is described in more detail below on the basis of a preferred embodiment with reference to the drawings. Show it:

Fig. 1

a front view of a conventional tennis racket according to the prior art;

Fig. 2

a side view of the conventional tennis racket of FIG. 1;

Fig. 3

a partial front view of one half of a preferred embodiment of the racket according to the invention;

4a to 4t

Sectional representations of various cross-sectional profiles along the section lines drawn in Fig. 3;

Fig. 5

an enlarged partial front view of a half of a preferred embodiment of the racket according to the invention, similar to Figure 3, wherein the axial relationships of the cross-sectional profiles are indicated at the respective interfaces;

Fig. 6

a schematic front view of a simplified embodiment of the racket according to the invention;

Fig. 7

a sectional view of the cross-sectional profile along the line VII-VII of Fig. 6;

Fig. 8

a sectional view of the cross-sectional profile along the line VIII-VIII of Fig. 6;

Fig. 9

a sectional view of the cross-sectional profile along the line IX-IX of Fig. 6;

Fig. 10

a sectional view of the cross-sectional profile along the line XX of Fig. 6;

Fig. 11

a sectional view of the cross-sectional profile along the line XI-XI of Fig. 6;

Fig. 12

6 shows a sectional illustration of the cross-sectional profile along the line XII-XII from FIG. 6.

In Figures 1 and 2 is a conventional tennis racket 2 in front and Side view shown. This tennis racket 2 essentially has one oval club head 4, a heart area 6 and a grip section 8. in the The head area 4 of the racket 2 is usually a recess 10 for receiving a wear frame or headgear, not shown, is provided. The Heart area 6 of the racket is essentially the connection area between the head region 4 and the grip section 8 and has, for example, as shown in Fig. 1, an opening 12. This opening is not mandatory required. However, if it is formed, it is separated by two side sections 14 and 16 and a connecting section or a bridge 18 in the head region 4 the racket 2 formed. For strength reasons, can be between the two Side areas 14 and 16 of the heart area 6 a second connecting element 20 may be provided.

The conventional tennis racket 2 shown in Figures 1 and 2 is off a shape profile with substantially constant dimensions, apart from the recess 10, formed. The cross-sectional shape or the Cross-sectional dimensions of the profile forming the racket frame are from Side area 14 of the heart area 6 around the head area 4 and to Side region 16 is substantially constant and oval or rectangular. Only in The receiving area of the connecting element 18 has the racket 2 reinforced Cross-sectional dimensions.

In the front view of the tennis racket 2 shown in Fig. 1 is in Head area 4 a dial of a conventional watch drawn in order below the racket according to the invention more easily with reference to the respective circumferential position on the head area 4 of the racket in connection with to be able to describe the corresponding time. For example, corresponds thus twelve o'clock an extreme head end 22 of the one shown in FIG. 1 Racket.

A preferred embodiment of a racket 30 according to the invention is shown in FIG Figures 3 to 5 shown. The racket 30 according to the invention corresponds in FIG its basic structure is essentially a conventional tennis racket, such as described above with reference to Figures 1 and 2. The means that the racket 30 according to the invention also has a head region 32, has a heart area 34 and a handle portion. The heart area 34 of the Racket 30 according to the invention can also be used contrary to that shown in FIG. 3 Embodiment without opening 38, i.e. the handle section can run closed up to the head area 32. Even the connecting element or the bridge 40 between the handle-side end sections 42 of the head region 32 is optional. Consequently, the heart area 34 can only be made from extensions 46 of the handle-side ends 42 of the head region 32, which extend towards the handle section extend, be formed.

As already explained above, the racket 30 according to the invention is the The basic idea is that the profile forming the frame corresponds to the occurring at the individual frame positions (main) Strains has different cross-sectional shapes to the have moments of resistance adapted to the respective types of stress. The The term "cross section" in the sense of the present invention refers to a Section through the frame profile of the racket along a plane that is in the essentially normal or perpendicular to a tangential plane on a Outer surface of the frame at the interface and essentially normal or perpendicular to a plane parallel to the stringing plane of the racket extends.

A preferred embodiment of the tennis racket according to the invention described below with reference to Figures 3 to 5. In this Context should be noted that this example is not meant to be limiting or exclusive embodiment of the present invention but rather represents the currently preferred embodiment.

The enlarged partial front view shown in Figure 3 Racket 30 of this embodiment of the invention shows only one Half of a head area 32 and a heart area 34. The other, not shown racket half is preferably symmetrical. The in Figure 3 cut lines a-a, b-b, c-c, etc. through the cross section of the racket profile are essentially at a distance of about 30 mm arranged. The cuts n-n to are only in the heart area 34 of the racket t-t at other intervals according to the maximum occurring there Stresses arranged. The cross-sectional profiles along the individual Sections of the preferred embodiment of racket 30 are in the figures 4a to 4t. The height of the racket frame according to the invention is in the preferred embodiment preferably continuously between 20 and 35 mm, preferably 28.5 mm.

The cross-sectional profiles shown in Figures 4a to 4t are with the respective Cross-sectional width dimensioned at the individual interfaces so that together with the constant preferred height of 28.5 mm specific axis ratio of the essentially elliptical cross-sectional profiles sets. This axis ratio is in each case shown Cross-sectional profiles specified at the individual cutting positions. Out For better clarity, the individual axis relationships are in Figure 5 displayed again directly at the individual interfaces.

For example, in areas that are subject to particularly high bending stress Racket in the range of about two o'clock to four o'clock, i.e. in the range between the sections g-g and l-l a rather rectangular cross-sectional profile with a Axis ratio in the range of 1.93 to 1.61 provided. To accommodate Torsional stresses are essentially circular Cross-sectional profile particularly well suited. Such a cross-sectional profile is for example in the range from about half past four to half past seven, i.e. in the Find the range of cuts n-n, o-o and p-p. That’s moving there Axis ratio in the range between 1.05 and 1.32. In the grip and Heart area 34 of the racket is due to the high occurring there Bending stresses have a substantially rectangular cross-sectional profile, such as it e.g. is shown in Figures 4q, 4r and 4s, particularly preferred. At a club type having a bridge 40 is however due to the given the stiffening bridge 40 also a different cross-sectional shape, e.g. Circular or elliptical shape possible.

In the area of the tip of the club head, i.e. So in the range from twelve o'clock to about one thirty or two o'clock, is preferably an elliptical Cross-sectional profile provided. In addition, it is advantageous that Frame width towards the outermost head region 50 of the racket 30 reduce, so that here are particularly slim frame shapes to let. This is shown in Figures 4a to 4f. The axis ratio in The range of the cuts a-a to f-f preferably ranges between 2.05 and 2.59. There is preferably between the different cross-sectional profiles a continuous transition is envisaged.

The racket 30 according to the invention described above represents a particularly preferred embodiment of the present invention, this is however, not to those specified in FIGS. 4a to 4t and FIG. 5 Axis ratios and dimensions limited. Rather, in the field of present invention these dimensions and ratios depending on the application vary. Such is the racket 30 described in FIGS. 3 to 5 for example a tennis racket for which these dimensions and axis relationships are particularly preferred. However, the responsible specialist is without further be clear that, for example, for a squash racket others Dimensions and axis relationships can be advantageous.

As explained above, those indicated in FIGS. 4a to 4t Axis ratios are only preferred information. These ratios can in a range of ± 20% and particularly preferably in a range of Vary ± 10%.

In the preferred embodiment of the racket 30 according to the invention also in the range from about four to six o'clock or in the heart region 34 one or several bump-like bulges or reinforcements are provided. According to FIGS. 3 to 5 each have a bump-like curvature at the section n-n and p-p 51 and 53 provided. These bulges 51 and 53 are particularly for Absorption of particularly high stresses occurring at these points educated. In this curved area, the axis ratio approaches one on, i.e. the cross-sectional profile is approximately rounded square. Although it is preferred, approximately in the vicinity of the heart region 34 of the invention Racket 30 to provide two such bump-like stiffening elements these are only optional. However, it is advantageous, at least in this area to provide one of these bumps, preferably two or more. In particular is it is advantageous to put two pairs of such stiffening elements on the racket provide axisymmetric arrangement.

In the following reference is made to FIGS. 6 to 12. There will be one simplified embodiment of the racket 30 according to the invention described.

One particularly adapted, for example, to torsional stresses The cross-sectional shape is an essentially circular or elliptical hollow profile. Such a hollow profile is shown, for example, in FIGS. 8, 10 and 12, each along the cross-sectional profile of the racket 30 according to the invention lines VIII-VIII at about one thirty, X-X at about five and, XII-XII in Represent heart area. For those shown in Figures 8, 10 and 12 Ellipse profile is an axis ratio of the axes L: 1 in the range between 26:15 to 30:15 and particularly 28:15. The section shown in Fig. 6 VIII-VIII is approximately in the range between one and two o'clock and in particular about one thirty. The section line X-X in FIG. 6 runs approximately between four and six o'clock and especially at five o'clock. It has been under the Invention shown that surprisingly particularly high in this area outward torsional moments occur in Fig. 6 by the two Arrows A are symbolized. These are outward torsional moments especially surprising because it would actually be expected that upon impact of a ball on a head, not shown, 32 of the Racket 30 provided covering the frame section in the area of the cut X-X twisted inwards. In the area of the cutting lines XI-XI and XII-XII is due to the high moments occurring there in the heart area 34 of the Racket according to the invention preferred a rectangular profile, because of Stiffening through the bridge can also, as shown in the Embodiment, a circular or elliptical profile for the cross-sectional shape of the Frame or the two frame webs 46 and 48 may be provided.

For racket areas in which bending stresses predominantly occur, an essentially rectangular hollow profile is particularly preferred. Such a rectangular hollow profile has a high moment of bending resistance and is therefore particularly suitable for absorbing bending stresses. Such bending stresses occur at the club head 32, particularly in the area of the section line IX-IX, ie between two and four o'clock. Consequently, between the two circular or elliptical hollow profiles on the section lines VIII-VIII and XX, a rectangular cross section is provided in the area of the section line IX-IX, the profiles preferably flowing smoothly or continuously into one another. The aspect ratio L ₉ : l ₉ is preferably about 2.5 to 3.5 and in particular about 3.

At an outermost head end 50 of head portion 32 is shown in Fig circular or elliptical profile illustrated 8 preferably to a narrower ellipse profile with an axial ratio of ₈ L: tapered. 9: l ₈ between 2.5 and 3.5 and in particular of about 28. This is particularly advantageous in order to achieve a low overall height.

A narrower ellipse profile corresponding to FIG. 11 can also be provided between the ends 42 and 44 of the head region 32 facing the handle section 36, which have the circular or elliptical profile according to FIG. 10, and the circular or elliptical profile along the line XII-XII . The axis ratio L ₁₁ : L ₁₁ in this range is preferably between 2.5 and 3.5 and in particular about 3.

All transitions between the different profile types and - Dimensions are preferably fluid, so that dangerous Voltage peaks in the frame can be avoided. The Racket 30 according to the invention is also in relation to a central axis 52 essentially symmetrical, so that the above described Cross-sectional profiles between zero and six o'clock at appropriate points between twelve and six o'clock.

Although for the racket 30 according to the invention Cross-sectional profiles without a recess or recess for one Wear frame or a headband are shown, such Indentation around a substantial part of the outer circumference of the club head 32 may be provided.

All known materials for the racket 30 according to the invention are known Materials for tennis, squash, badminton and other rackets for Suitable for ball sports. In particular, the racket 30 according to the invention is made of Wood, metal, metal alloys, plastics, composite materials and Combinations can be made from it.

Claims (20)

Racket (30) for ball games with a racket head (32), one Handle section (36) and one between the club head (32) and the Frame (34) provided with the grip section (36), with a profile forming the frame at different Frame positions according to the ones that occur there Main types of stress has different cross-sectional shapes, the resistance moments adapted to the respective types of stress to have. The racket of claim 1, wherein at least two bump-like on the frame Stiffening elements (51, 53) are formed. The racket of claim 2, wherein a first bump-like Stiffening element (53) in the range between four and six o'clock and one second bump-like stiffening element essentially symmetrical in addition between six and eight o'clock on an opposite Racket side is provided. Racket according to one of claims 2 or 3, wherein four bump-like Stiffening elements (51, 53) are provided, of which a first pair in the range between four and six o'clock and a second pair in essentially symmetrical between six and eight o'clock on one opposite club side is formed. Racket according to one of claims 2 or 3, wherein four bump-like Stiffening elements (51, 53) are provided, of which a first pair with a stiffening element (53) in the range between four and six o'clock and with a stiffening element (51) on the heart area (34) of the racket (30) and a second pair substantially symmetrical to it is. Racket according to one of claims 2 to 5, wherein the axis ratio in Range of a bump-like stiffening element (51, 53) between 1.0 and 1.4, preferably between 1.2 and 1.35. The racket of any of claims 1 to 6, wherein the cross-sectional widths from twelve to about three o'clock and symmetrically between twelve and nine Clock gradually get bigger. The racket of one of claims 1 to 7, wherein the on Bending stresses adapted cross-sectional shape an approximate is rectangular hollow profile. Racket according to one of claims 1 to 8, wherein the on Torsional stresses adapted cross-sectional shape essentially is circular or elliptical hollow profile. The racket of claim 8 or 9, wherein the rectangular profile Aspect ratio of 2.5 to 3.5 and preferably 3.0. The racket of claim 9 or 10, wherein the elliptical profile is a Axis ratio L: l from 26:15 to 30:15 and preferably from 28:15. Racket according to one of claims 8 to 11, wherein the rectangular profile in Area of the club head between two and four o'clock and between eight and ten o'clock and the circular or elliptical profile in the area of Club head between ten and two o'clock is formed. The racket of claim 12, wherein the rectangular profile in the area of Club head is trained at three and nine o'clock. Racket according to one of claims 8 to 13, wherein the circular or Ellipse profile is formed in the area between about four and eight o'clock. Racket according to one of claims 1 to 14, wherein the frame forming profile is hollow. Racket according to one of claims 1 to 15, wherein in the range of outermost head end (50) in the head area (32) between eleven and one o'clock Ellipse profile with an axis ratio L: l of 2.5 to 3.5 and preferably of 28: 9 is provided. Racket according to one of claims 1 to 16, wherein in the heart region (34) Rectangular, circular or elliptical profile is formed. Racket according to claim 17, wherein the circular or elliptical profile in Heart area (34) away from the head area (32) Axis ratio has. Racket according to one of claims 1 to 18, wherein the individual shapes the cross-sectional profiles merge smoothly. Racket according to one of claims 1 to 19, wherein in an outer edge of the club head (32) at least in sections a recess for Recording a headband is provided.

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