BALL GAME RACKET FRAME WITH IMPROVED TORSION

Abstract

The present invention relates to a ball game racket frame with improved torsional behavior.

Claims

1. A ball game racket frame comprising a head portion (1), a handle portion (2) and a throat (3) connecting the head portion (1) to the handle portion (2) and comprising two throat beams (4), wherein each of the throat beams (4) merges into the handle portion (2) at a respective first transition cross-section (5) and merges into the head portion (1) at a respective second transition cross-section (6), wherein, at a distance of 10 mm from the respective first transition cross-section (5), each of the throat beams (4) has a first cross-sectional profile (7) having a first frame width (A) and a first frame height, wherein, at a distance of 10 mm from the respective second transition cross-section (6), each of the throat beams (4) has a second cross-sectional profile (8) having a second frame width (B) and a second frame height, wherein the ratio of the second frame width (B) to the first frame width (A) is at least 1.15 and the longitudinal extension (C) of the throat (3) is at least 105 mm.

2. The ball game racket frame according to claim 1, wherein the ratio of the second frame width (B) to the first frame width (A) is at least 1.20.

3. The ball game racket frame according to claim 1, wherein the longitudinal extension (C) of the throat (3) is at least 110 mm.

4. The ball game racket frame according to claim 1, wherein the first frame width (A) is at most 13.0 mm.

5. The ball game racket frame according to claim 1, wherein the first frame width (A) is at most 12.0 mm.

6. The ball game racket frame according to claim 1, wherein the ratio of the second frame height to the first frame height is at most 1.25.

7. The ball game racket frame according to claim 1, wherein the ratio of the second frame height to the first frame height is at most 1.20.

8. The ball game racket frame according to claim 1, wherein the second frame width (B) is at most 20.0 mm.

9. The ball game racket frame according to claim 1, wherein the second frame width (B) is at most 18.0 mm.

10. A ball game racket frame comprising a head portion (1), a handle portion (2) and a throat (3) connecting the head portion (1) to the handle portion (2) and comprising two throat beams (4), wherein each of the throat beams (4) merges into the handle portion (2) at a respective first transition cross-section (5) and merges into the head portion (1) at a respective second transition cross-section (6), wherein, at a distance of 10 mm from the respective first transition cross-section (5), each of the throat beams (4) has a first cross-sectional profile (7) having a first frame width (A) and a first frame height, wherein, at a distance of 10 mm from the respective second transition cross-section (6), each of the throat beams (4) has a second cross-sectional profile (8) having a second frame width (B) and a second frame height, wherein the ratio of the second frame width (B) to the first frame width (A) is at least 1.10 and the first frame width is at most 12.5 mm.

11. The ball game racket frame according to claim 10, wherein the first frame width (A) is at most 12.0 mm.

12. The ball game racket frame according to claim 10, wherein the longitudinal extension (C) of the throat (3) is at least 100 mm.

13. The ball game racket frame according to claim 10, wherein the longitudinal extension (C) of the throat (3) is at least 105 mm.

14. The ball game racket frame according to claim 10, wherein the ratio of the second frame width (B) to the first frame width (A) is at least 1.15.

15. The ball game racket frame according to claim 10, wherein the ratio of the second frame height to the first frame height is at most 1.25.

16. The ball game racket frame according to claim 10, wherein the ratio of the second frame height to the first frame height is at most 1.20.

17. The ball game racket frame according to claim 10, wherein the second frame width (B) is at most 20.0 mm.

18. The ball game racket frame according to claim 10, wherein the second frame width (B) is at most 18.0 mm.

19. The ball game racket frame according to claim 1, wherein the first frame height is at most 26.0 mm.

20. The ball game racket frame according to claim 1, wherein the second frame height is at most 25.0 mm.

21. The ball game racket frame according to claim 10, wherein the first frame height is at most 26.0 mm.

22. The ball game racket frame according to claim 10, wherein the second frame height is at most 25.0 mm.

Description

[0024] In the following, a preferred embodiment of the ball game racket frame according to the invention is described in more detail with reference to the Figures, in which:

[0025] FIG. 1 shows a schematic top view of a part of a ball game racket frame according to a preferred embodiment; and

[0026] FIG. 2 shows a table with various measurements of the ball game racket frame according to FIG. 1 as well as of various ball game racket frames from the prior art.

[0027] FIG. 1 shows a schematic top view of a part of a ball game racket frame according to a preferred embodiment of the present invention. The ball game racket frame comprises an only partially shown head portion 1, which receives the strings, which are not depicted, and comprises the bridge 9 at its lower end, an only partially shown handle portion 2 and a throat 3 connecting the head portion 1 with the handle portion 2. The throat 3 comprises two throat beams 4 which, together with the bridge 9, form the so-called heart with the inner region 10 of the ball game racket frame.

[0028] Each of the throat beams 4 merges into the handle portion 2 at a respective first transition cross-section 5 and merges into the head portion 1 at a respective second transition cross-section 6. According to the invention, the first transition cross-section 5 is defined such that it touches or is tangent to the lowest point of the inner region 10 formed by the throat 3. In other words, the first transition cross-section 5 is the cross-section which is displaced furthest from the handle portion 2 towards the head portion 1 and extends perpendicularly to the longitudinal axis of the racket and has no opening resulting from the inner region 10. Analogously, the second transition cross-section 6 is defined according to the invention such that it just touches or is tangent to the upper, outer edge 12 of the inner region 10. In other words, the second transition cross-section 6 is the cross-section that can be displaced furthest from the head portion 1 towards the handle portion 2 so that it does not contain any opening resulting from the inner region 10 and extends perpendicularly to the contour of the corresponding throat beam 4.

[0029] According to the invention, each of the throat beams 4 has a first cross-sectional profile 7 with a first frame width A and a first frame height at a distance of 10 mm from the respective first transition cross-section 5 and a second cross-sectional profile 8 with a second frame width B and a second frame height at a distance of 10 mm from the respective second transition cross-section 6. The distance is determined in each case, as shown in FIG. 1, on the outside of the throat beams 4. In other words, starting from the plane formed by the first transition cross-section 5, the point on the outside of the throat beam 4 is determined which has a distance of 10 mm from this very plane. This point is then to be part of the first cross-sectional profile 7. An analogous procedure is followed with the second cross-sectional profile 8. According to the invention, the ratio of the second frame width B to the first frame width A is to be at least 1.15.

[0030] According to a first aspect of the invention, the longitudinal extension C of the throat 3 is furthermore intended to be at least 105 mm. The longitudinal extension C of the throat 3 denotes the inner length of the throat, which, as shown in FIG. 1, is measured from the lowest point 11 of the inner region 10 formed by the throat 3 to the lower edge of the bridge 9. The measurement is made along the central longitudinal axis of the ball game racket frame. In other words, the longitudinal extension C of the throat 3 corresponds to the length of the inner region 10 of the racket heart.

[0031] The first frame height (hereinafter also referred to as D) as well as the second frame height (hereinafter also referred to as E), which are not shown in FIG. 1, are respectively measured in the first cross-sectional profile 7 and in the second cross-sectional profile 8 perpendicularly to the drawing plane of FIG. 1, i.e. perpendicularly to the string bed plane. Since the cross-sectional profiles of throat beams are generally not rectangular but have, for example, curves, the first and second frame widths as well as the first and second frame heights are, according to the invention, the maximum extensions of the corresponding cross-sectional profiles parallel to the string bed plane and perpendicular to the string bed plane, respectively.

[0032] The applicant has measured a preferred embodiment of the ball game racket according to the invention, which is to be launched on the market under the model name “Boom MP” in the year 2022. The corresponding values for the first frame width A, the second frame width B, the first frame height D, the second frame height E and the longitudinal extension C of the throat as well as the ratios B/A and E/D are revealed in the table according to FIG. 2. Furthermore, the applicant has measured a number of further tennis racket frame models of various brands. The corresponding values are also revealed in the table according to FIG. 2.

[0033] Each of the ball racket frames was unstrung during the measurement, and the grommet strip in the heart bridge was dismantled for the measurement of the longitudinal expansion of the throat.

[0034] As revealed by the table in FIG. 2, the ball game racket frame according to the invention very clearly differs in the ratio of the second frame width B to the first frame width A from almost all ball game racket frames from the prior art.

[0035] Only the “Ghost” model from the supplier Donnay exhibits a comparable ratio of 1.38 (cf. also the corresponding applications EP 0 671 186 A1 and U.S. Pat. No. 5,299,801). However, this prior art model has a significantly shorter longitudinal extension of the throat of only 94 mm and a significantly larger frame width A of 12.86 mm. Therefore, this ball game racket frame does not exhibit the desired torsional properties because all in all the racket heart of this ball game racket frame is too stiff.

[0036] Furthermore, there were two models from Head (“Airflow 1” and “Airflow 3”) which exhibited a significantly larger B/A ratio of 1.73 and 1.61 respectively (see also DE 10 2006 004 863 B4). However, these models had extremely dimensioned throats with first frame widths and heights at the transition to the handle of around 14 mm and around 26 mm, respectively, which also prevented the desired torsion.

[0037] During initial tests with a prototype, test players reported that the “Boom™” model ball racket frame gave them a very good feel for the deformation of the frame, which they said gave them better control over their own game.