Abstract
The present invention relates to a ball game racket, a method for adjusting the length of the handle portion of a ball game racket and a handle shell for the handle portion of a ball game racket.
Claims
1. A ball game racket comprising a racket head and a handle portion, wherein the handle portion comprises a handle core being integrally connected to the handle head and having an outer side and a handle shell having an inner side, wherein the outer side of the handle core can be engaged with the inner side of the handle shell at different discrete relative positions with respect to the longitudinal axis of the ball game racket in such a positive locking and/or friction locking that the positive and/or friction locking provides for a connection between the handle shell and the handle core that can be disconnected in a destruction-free manner, wherein the handle core has a plurality of projections and/or depressions which are offset with respect to each other in the longitudinal direction and wherein the handle shell has a plurality of corresponding depressions and/or projections which are offset with respect to each other in the longitudinal direction and can be engaged with the projections and/or depressions of the handle core, wherein the handle core has more projections and/or depressions than the handle shell.
2. The ball game racket according to claim 1, further comprising a grip tape which is wound around the handle shell and thus additionally attaches the handle shell to the handle core in such a manner that the connection can be disconnected in a destruction-free manner.
3. The ball game racket according to claim 1, wherein the connection between the handle shell and the handle core can be disconnected without the use of tools.
4. The ball game racket according to claim 1, wherein the positive and/or friction locking can be realized at at least three different relative positions with respect to the longitudinal axis of the ball game racket.
5. The ball game racket according to claim 1, wherein the positive and/or friction locking is substantially a positive locking and can be realized at different discrete relative positions with respect to the longitudinal axis of the ball game racket, wherein the offset between adjacent relative positions is at most 10 mm.
6. The ball game racket according to claim 1, wherein the distance between adjacent projections and/or depressions which are offset with respect to each other in the longitudinal direction is substantially constant.
7. The ball game racket according to claim 6, wherein the distance between adjacent projections and/or depressions which are offset with respect to each other in the longitudinal direction is at most 10 mm.
8. The ball game racket according to claim 1, wherein the handle core comprises a distal end facing the racket head, a proximal end facing away from the racket head and a central portion, wherein the central portion is spaced from the proximal end by at least 2 cm and wherein at least some projections and/or depressions are provided in said central portion.
9. The ball game racket according to claim 8, wherein the central portion is spaced from the distal end by at least 3 cm.
10. The ball game racket according to claim 1, wherein the handle core has a substantially octagonal cross-sectional profile with four short edges and four long edges and wherein the outer surfaces of the handle core which form the four short edges of the cross-sectional profile comprise at least some projections and/or depressions.
11. The ball game racket according to claim 1, wherein the distance between adjacent projections and/or depressions at the handle core, which are offset with respect to each other in the longitudinal direction, is smaller than the distance between adjacent depressions and/or projections at the handle shell, which are offset with respect to each other in the longitudinal direction.
12. The ball game racket according to claim 1, wherein the handle shell comprises two half shells which are connected with each other at an end in a hinged and/or flexible manner.
13. The ball game racket according to claim 12, wherein at least one dampening element is provided between the half shells.
14. The ball game racket according to claim 1, wherein the handle shell comprises a handle cap which is an integral element of the handle shell, wherein the handle cap has a receiving portion for releasably receiving an electronic component.
15. A method for adjusting the length of the handle portion of a ball game racket according to claim 1, the method comprising the following steps: (a) disconnecting the connection between the handle shell and the handle core; (b) adjusting the relative position between handle core and handle shell by repositioning the handle shell with respect to the longitudinal axis of the ball game racket; and (c) engaging the outer side of the handle core with the inner side of the handle shell in the adjusted relative position in order to connect the handle shell to the handle core.
16. The method according to claim 15, further comprising the steps of winding off the grip tape before step (a) and winding a grip tape around the handle shell after step (c).
17. The method according to claim 15, wherein step (a) is carried out in a destruction-free manner and wherein step (c) is carried out without using an adhesive.
18. The method according to claim 15, wherein step (a) is carried out in a tool-free manner and wherein step (c) is carried out without using an adhesive.
19. A ball game racket comprising a racket head and a handle portion, wherein the handle portion comprises a handle core being integrally connected to the handle head and having an outer side and a handle shell having an inner side, wherein the outer side of the handle core can be engaged with the inner side of the handle shell at different discrete relative positions with respect to the longitudinal axis of the ball game racket in such a positive locking and/or friction locking that the positive and/or friction locking provides for a connection between the handle shell and the handle core that can be disconnected in a destruction-free manner, wherein the handle core has a plurality of projections and/or depressions which are offset with respect to each other in the longitudinal direction and wherein the handle shell has a plurality of corresponding depressions and/or projections which are offset with respect to each other in the longitudinal direction and can be engaged with the projections and/or depressions of the handle core, wherein the distance between adjacent projections and/or depressions at the handle core, which are offset with respect to each other in the longitudinal direction, is smaller than the distance between adjacent depressions and/or projections at the handle shell, which are offset with respect to each other in the longitudinal direction.
20. A ball game racket comprising a racket head and a handle portion, wherein the handle portion comprises a handle core being integrally connected to the handle head and having an outer side and a handle shell having an inner side, wherein the outer side of the handle core can be engaged with the inner side of the handle shell at different discrete relative positions with respect to the longitudinal axis of the ball game racket in such a positive locking and/or friction locking that the positive and/or friction locking provides for a connection between the handle shell and the handle core that can be disconnected in a destruction-free manner, wherein the handle core has a plurality of projections and/or depressions which are offset with respect to each other in the longitudinal direction and wherein the handle shell has a plurality of corresponding depressions and/or projections which are offset with respect to each other in the longitudinal direction and can be engaged with the projections and/or depressions of the handle core, wherein the handle core has a substantially octagonal cross-sectional profile with four short edges and four long edges and wherein the outer surfaces of the handle core which form the four short edges of the cross-sectional profile comprise at least some projections and/or depressions.
Description
(1) In the following, preferred embodiments of the present invention are described in more detail with reference to the Figures in which
(2) FIG. 1 shows a perspective view of the handle portion of a ball game racket according to a preferred embodiment of the present invention in which the handle shell is partly removed;
(3) FIG. 2 shows a schematic longitudinal sectional view of the handle portion of a ball game racket according to a preferred embodiment of the present invention;
(4) FIG. 3 shows a schematic longitudinal sectional view of the handle portion according to FIG. 2;
(5) FIG. 4 shows a schematic longitudinal sectional view of the handle portion of a ball game racket according to a preferred embodiment of the present invention;
(6) FIG. 5 shows a schematic perspective view of the handle portion of a ball game racket according to a preferred embodiment of the present invention;
(7) FIG. 6 shows a schematic longitudinal sectional view of a part of the handle portion of a ball game racket according to a preferred embodiment of the present invention;
(8) FIG. 7 shows a schematic cross-sectional view of the handle portion according to FIG. 1;
(9) FIG. 8 shows a schematic longitudinal sectional view of a part of the handle portion of a ball game racket according to a preferred embodiment of the present invention;
(10) FIG. 9 shows a perspective view of the handle core of a handle portion of a ball game racket according to a preferred embodiment of the present invention;
(11) FIG. 10 shows a perspective view of a handle half shell according to a preferred embodiment of the present invention;
(12) FIG. 11 shows a perspective view of the handle core and the handle shell of a handle portion of a ball game racket according to a preferred embodiment of the present invention; and
(13) FIG. 12 shows a perspective view of the handle portion of a ball game racket according to a preferred embodiment of the present invention with mounted handle shell.
(14) FIG. 1 shows a perspective view of the handle portion 1 of a ball game racket according to a preferred embodiment of the present invention. In addition to the handle portion 1, the ball game racket has a racket head (only indicated) which is connected to the handle portion 1 of the ball game racket by means of a heart region 9. The handle portion 1 comprises a handle core 2 being integrally connected to the racket head and having an outer side and a racket shell 3 (only partly shown in FIG. 1) having an inner side. The outer side of the handle core 2 can be engaged with the inner side of the handle shell 3 at different relative positions (one of them being shown in FIG. 1) with respect to the longitudinal axis of the ball game racket in such a positive locking that the positive locking provides for a connection between the handle shell 3 and the handle core 2 that can be disconnected in a destruction-free manner. In the shown preferred embodiment, this positive locking is realized in that the handle core 2 has a plurality of depressions 4 which are offset with respect to each other in the longitudinal direction (of the handle portion or the ball game racket) and the handle shell 3 has a plurality of corresponding projections 5 which are offset with respect to each other in the longitudinal direction and can be engaged with the depressions 4 of the handle core 2. This principle is schematically shown in FIGS. 2 and 3 in which the handle core 2 has three respective depressions or grooves 4 on two opposing outer surfaces and the two half shells 3a and 3b forming the handle shell 3 each have two projecting ribs or struts 5. These projecting ribs or struts 5 can be engaged with different depressions or grooves 4 of the handle core 2, as evident from a comparison of FIGS. 2 and 3, so that the outer side of the handle core 2 can be engaged in a positively locking manner with the inner side of the handle shell 3 at different relative positions with respect to the longitudinal axis of the ball game racket. Thus, in view of the starting position shown in FIG. 2, the effective length of the handle portion can be increased (see FIG. 3) in that the handle shell 3 projects in the proximal direction beyond the handle core 2. At the proximal end of the handle portion, a hollow space 10 is thus formed. In order for the latter not having a negative effect on the stability of the handle portion, it is preferred to make the handle shell 3 from a material that is as stable as possible, for example ABS. Further suitable materials include PET, PA, TPE, PC, PVC, PBT, PE, PP as well as their common blends. However, ABS is a particularly preferred material in view of its high impact resistance and its small moisture expansion. A further preferred material is Terblend (a mixture of ABS and PA).
(15) The distance d1 between adjacent depressions 4 in the handle core 2 is preferably at most 10 mm, more preferably at most 8 mm, even more preferably at most 6 mm and particularly preferably at most 5 mm. Moreover, it is preferred that the distance d1 is constant for all depressions 4 on one side of the handle core 2. Preferably, the distance d1 is also identical for different sides of the handle core 2. In the shown preferred embodiment according to FIGS. 2 and 3, the distance d2 between adjacent projections 5 is the same as the distance d1. The distances d2 of a half shell of the handle shell 3 are preferably constant. Moreover, it is preferred that the distances d2 in one half shell 3a are identical to the distances d2 in the second half shell 3b.
(16) However, the distance d2 between adjacent projections does not have to be equal to the distance d1 between adjacent depressions. For example, the distance d2 can be larger than the distance d1 and, in particular, correspond to an integer multiple of the distance d1. FIG. 6 only exemplarily shows an embodiment in which the distance d2 between adjacent projections 5a and 5b is twice as large as the distance d1 between adjacent depressions 4. The accuracy with which the offset between the handle shell 3 and the handle core 2 can be adjusted is determined by the distance d1: If the handle shell 3a is moved in the proximal direction so that the projections 5a and 5b engage with the depressions 4b and 4d, an offset by the distance d1 is achieved between the handle shell 3a and the handle core 3 as compared to the situation shown in FIG. 6. This leads to an easier and more cost-efficient manufacturing of the handle shell 3 because less projections having larger distances between each other must be produced. Of course also the reverse situation would be conceivable, in which less projections having larger distances between each other are provided in the handle core and more projections having smaller distances between each other in the handle shell. However, the option shown in FIG. 6 is preferred because the depressions in the handle shell can have a negative effect on its stability.
(17) A further relevant parameter is the overall distance D by which the handle shell 3 can be moved between the most distal position and the most proximal position. In FIG. 6, this overall distance D is defined by the distance between the depression 4c and the depression 4g and thus corresponds in the present embodiment to four times the distance d1 (provided that the two shown projections 5a and 5b are engaged with respective projections 4e and 4g). The minimum offset (which corresponds to the distance d1 in the embodiment of FIG. 6) is preferably at most 10 mm, more preferably at most 8 mm, even more preferably at most 6 mm and particularly preferably at most 5 mm. The maximum offset D is preferably at least 2 cm, more preferably at least 3 cm, even more preferably at least 4 cm and particularly preferably at least 5 cm.
(18) Basically, the projections and depressions can have any desired shape. However, it is preferred that the projections and depressions are present in the form of struts or elongate grooves extending in a direction transversely with respect to the longitudinal direction of the handle portion. The cross-section of these struts or grooves can also be arbitrary and can be, for example, rectangular (see FIG. 6), round (see FIGS. 4 and 5) or trapezoidal (see FIGS. 2 and 3). In view of a connection that is as simple as possible, a cross-section with tapering sides, such as, for example, the trapezoidal cross-section shown in FIGS. 2 and 3, is advantageous. The trapezoid can be symmetrical or asymmetrical, for example in order to account for different forces in the proximal and distal directions.
(19) A relatively small minimum offset using as little projections as possible can be achieved by means of different distances d1 and d2, as discussed above with reference to FIG. 6. Alternatively or additionally, the projections or depressions can also be arranged in different manners on different sides of the handle core 2 or in the different half shells 3a and 3b of the handle shell 3, as exemplarily shown in FIGS. 4 and 5. By rotating the handle shell 3 by 90 (see FIG. 5) or by 180 (see FIG. 4) about the longitudinal axis of the racket, different offsets of the handle shell with respect to the handle core can be achieved. Preferably, the offset between depressions 4a on one side of the handle core 2 and the adjacent depressions 4b on the opposite side of the handle core 2 (see FIG. 4B) corresponds to half the distance d1 between adjacent depressions 4 on one and the same side. Analogously, this also applies to the offset between adjacent depressions 4a on one side and adjacent depressions 4c on an adjacent side of the handle core 2, as shown in FIG. 5.
(20) In the embodiment of FIGS. 2 and 3, each of the projections 5 of the handle shell 3 is engaged with some of the depressions 4 of the handle core 2. This is also the case in the further embodiments according to FIGS. 4 to 6. However, this is not necessary, as shown in the preferred embodiment according to FIG. 1 and the schematic view according to FIG. 8. According thereto, the depressions 4 in the handle core 2 can be provided in a raised region (or can be formed by forming complementary projections). Along this raised region, a respective projection 5 is engaged with a corresponding depression 4. Outside this raised region, however, the respective projections 5 are not engaged with any of the depressions. Preferably, the length 11 of this raised region is larger than 4 cm, more preferably larger than 5 cm, even more preferably larger than 6 cm and particularly preferably larger than 7 cm. The length 12 of the region of the handle shell 3 in which projections 5 are provided is preferably larger than 6 cm, more preferably larger than 8 cm, even more preferably larger than 10 cm and particularly preferably larger than 12 cm. The distance of the raised region (or the central portion of the handle core in which projections and/or depressions are provided) from the proximal end 7 of the handle core is preferably at least 2 cm, more preferably at least 3 cm and particularly preferably at least 4 cm. The distance of the raised region or the central portion from the distal end of the handle core is preferably at least 3 cm, more preferably at least 5 cm and particularly preferably at least 7 cm.
(21) Since the shape of the handle portion sensed by the player is defined by the outer side of the handle shell, the cross-section of the handle core or the inner side of the handle shell can have any desired shape and can be, for example, rectangular or square. However, it turned out to be particularly advantageous that the handle core has a substantially octagonal cross-sectional profile (see FIG. 7) with four short edges 10 and four long edges 11a, 11b. It is preferred that the outer surfaces of the handle core 2 which form the four short edges 10 of the cross-sectional profile comprise the projections and/or depressions, as shown in FIG. 1. It is preferred that all four outer surfaces forming the short edges 10 have projections and/or depressions. Moreover, it is preferred that the outer surfaces of the handle core which form the remaining edges 11a and 11b do not have any projections and/or depressions.
(22) FIGS. 9 to 12 show different views of a handle portion of a ball game racket according to a preferred embodiment of the present invention. FIG. 9 shows the handle core 2 including its proximal end 7 with a substantially octagonal cross-sectional profile with four short edges 10 and four long edges 11a, 11b. In the shown preferred embodiment, all four outer surfaces of the handle core 2 which form the four short edges 10 of the cross-sectional profile have depressions 4 having an approximately trapezoidal cross-sectional profile with rounded corners. In the shown preferred embodiment, each outer surface has 13 depressions 4. The present invention is of course not restricted to a specific number of depressions, but it is also possible to provide more or less than 13 depressions. However, it is preferred that at least six, more preferably at least eight, even more preferably at least ten and particularly preferably at least twelve depressions are provided per outer side, wherein it is not necessary that all outer sides and all outer sides forming the short edges have depressions.
(23) FIG. 10 shows, as counterpart to the handle core 2 according to FIG. 9, a handle half shell 3a with a corresponding half 8a of a handle cap, which is integrally formed with the handle half shell 3a. In the regions which are engaged with the short edges of the handle core 2, the inner side of the handle half shell 3a has five respective projections 5 which are configured such that they can engage in a positive locking with the depressions 4 of the handle core 2. The present invention is of course not restricted to a specific number of projections, but it is also possible to provide more or less than five projections. However, it is preferred that at least two, more preferably at least three, even more preferably at least four and particularly preferably at least five projections are present per region, wherein each half shell can also have only one region with projections. The inner side of the handle half shell 3a can comprise further strengthening ribs or webs 12 which, however, are not adapted to engage with the depressions 4 of the handle core 2. Rather, they serve for stabilizing the handle half shell.
(24) FIG. 11 shows the individual components of the handle portion of a ball game racket according to a preferred embodiment of the present invention, comprising a handle core 2 (according to FIG. 9), two handle half shells 3a and 3b (according to FIG. 10) as well as a handle cap cover 8c which, together with the two halves 8a and 8b of the handle cap, forms the handle cap. Even if a separate handle cap cover 8c is provided in this embodiment, it is also possible that the handle cap cover is formed integrally with one of the two halves 8a and 8b of the handle cap. Alternatively, it is possible that each of the two halves 8a and 8b of the handle cap comprises also a part, preferably a half, of the handle cap cover.
(25) FIG. 12 shows the finished handle portion being mounted from the components according to FIG. 11. It is evident that the handle core 2 is completely enclosed by the two handle half shells 3a and 3b and the handle cap cover 8c, so that the handle core 2 is only visible distally of the distal end 6 of the handle shell 3 (not shown in FIG. 12). Preferably, the distal end 6 of the handle shell 3 tapers conically, as shown in FIGS. 11 and 12, in order to provide for a transition between handle shell 3 and handle core 2 that is as stepless as possible.
