EP0304317A1

EP0304317A1 - Tennis practice aid

Info

Publication number: EP0304317A1
Application number: EP88307700A
Authority: EP
Inventors: Andrew William Roger Dofel
Original assignee: CHRYMAT PTY Ltd
Current assignee: CHRYMAT PTY Ltd
Priority date: 1987-08-19
Filing date: 1988-08-19
Publication date: 1989-02-22
Also published as: JPH01158977A

Abstract

A tennis practice aid 10 having a frame 11 supporting a mesh 12 against which a ball impacts to be returned to the user, secured to the mesh 12 are rebound dampers 26 which influence the projection and/or velocity of a rebounding ball which impacts against the dampers 26 or adjacent thereto, in order to vary the ball return.

Description

The present invention relates to sports aids which provide a rebound surface for a ball, and more particularly but not exclusively to a tennis practice aid.
There are commercially available tennis practice aids which provide a rebound surface in the form of a flexible sheet material or solid surface The surfaces are basically upwardly extending and planar. However, rebound surfaces having a non-planar configuration, are disclosed in Australian Applications 71012/87 (USA Application No. 033 224 filed 1 April 1987).
Typical rebound surfaces are described in US Patents 4 489 941; 4 239 235; 3 563 455; 3 180 643; 2 333 098; as well as British Patent 18900 and German Patent 2 248 933. The devices disclosed in these publications all possess a rebound surface which is uniform and accordingly, the rebound qualities of the ball are predictable. Although in some instances the rebound surface may be divided into sub-surfaces, again the sub-surfaces are generally uniform and accordingly the return qualities of the ball are again predictable.
The above discussed rebound surfaces which are of a woven mesh (or sheet material) or provided by a solid surface, have the disadvantage that the ball return is substantially predictable and therefore does not similate a true tennis return where the opponent tries to vary the type of shot played.
It is the object of the present invention to overcome or substantially ameliorate the above disadvantage.
There is disclosed herein a rebound device for a ball game, said device comprising a frame to rest upon a support surface, a rebound surface supported by the frame and against which the ball may be hit to be returned to a user, said rebound surface being defined by a generally planar sheet material which is deformed by the ball impacting thereagainst, and rebound varying means fixed to said rebound surface and adapted to influence the projection and/or velocity of a rebounding ball having impacting against the rebound surface at or adjacent said rebound varying means as compared to a ball impacting against said rebound surface at a position remote from said rebound varying means.
There is further disclosed herein a rebound damper to be fixed to a flexible rebound sheet of a rebound device, which sheet has a front rebound surface against which a ball impacts to be returned by the device, and a rear surface; said damper having:
a head portion to abut said rebound surface so as to project away from said rebound surface;
a securing portion to abut said rear surface;
a neck joining said head portion and securing portion, which neck portion is adapted to pass through said rebound sheet; and
wherein said head portion has outwardly facing surface irregularities which engage the ball to vary the projection and/or velocity of the rebounding ball.
A preferred form of the present invention will now be described by way of example with reference to the accompanying drawings, wherein:

Figure 1 is a schematic perspective view of a tennis practice aid;
Figure 2 is a schematic perspective view of the net base portion of the tennis practice aid of Figure 1;
Figure 3 is schematic front perspective view of a rebound damper employed with the tennis practice aid of Figure 1;
Figure 4 is a schematic rear perspective view of the rebound damper of Figure 3;
Figure 5 is a schematic front elevation of the rebound damper of Figure 3;
Figure 6 is a schematic rear elevation of the rebound damper of Figure 3;
Figure 7 is a schematic side elevation of the rebound damper of Figure 3;
Figure 8 is a schematic sectioned side elevation of the rebound damper as illustrated in Figure 5 sectioned along the line 8-8;
Figure 9 is a schematic side elevation of the rebound damper of Figure 5 as sectioned along the line 9-9; and
Figure 10 schematically depicts various rebound dampers which may be used in combination with, or as alternatives to, the rebound damper of Figures 3 to 9.

In Figures 1 and 2 there is schematically depicted a tennis practice aid 10 to rest on a ground surface. The tennis practice aid 10 consists of a frame 11 which supports a sheet of woven mesh 12 providing a rebound surface 15 against which a tennis ball is hit, to return the tennis ball to the user. When the tennis ball impacts against the mesh 12, the mesh 12 is deformed and deflected thereby.
The frame 11 includes a rectangular sub-frame 13 which directly supports the mesh 12. The frame 11 further includes a pair of upright frame members 14 which directly support the sub-frame 13 and attach to the net base 16. The rectangular sub-frame 13 includes horizontal frame members 17 and vertical frame members 18. The frame members 14 are attached adjacent their upper and lower portions to the vertical frame members 18.
The net base 16 includes a frame 19 which includes two side sub-frames 20 of generally triangular configuration, with each sub-frame 20 having a wheel 21. A cross member 22 extends between the two sub-frames 20, as well as a pair of brace members 23.
Extending between the sub-frames 19 and 20 is a net 24 which has its upper edge positioned so as to approximate the upper edge of a normal tennis net.
The frame members 14 are telescopically received within the tubular portions 25 of the sub-frames 19 and 20. Accordingly, the frame 11 may be removed from the net base 16 so that the net base 16 may be used solely as a net with a player on each side. This configuration is depicted in Figure 2.
Mounted on the mesh 12 is a plurality of rebound dampers 26, described in more detail with reference to Figures 3 to 9.
The rebound dampers 26 have a head portion 27 and a securing portion 28 joined by a neck 29. The head portion 12 is provided with surface irregularities 30 in the form of projections 31 which extend away from the mesh 12. In this particular embodiment, the projections 31 are ridges which extend radially from the centre of the head portion 27. The projections 31 have longitudinally extending apexes 32, with the cross section of each projection 31 diminishing radially from the centre of the head portion 27. Preferably, each projection 31 has generally planar side surfaces 33 inclined by an angle of approximately 50 to 70 degrees, but more preferably 60 degrees. In this particular embodiment, there are five projections 31.
Defined between the head portion 27 and the securing portion 28 is an annular recess 34 within which strands 35 of the mesh 12 are located so that the rebound damper 26 is secured in position. Preferably the rebound damper 26 is moulded from plastics material or a natural or synthetic rubber.
The rebound damper 26 can be arranged in any desired pattern on the mesh 12.
In use of the above described tennis practice aid 10, a user upon directing a ball at the mesh 12, will not be able to anticipate all the ball returns since a ball impacting against or adjacent one of the rebound dampers 26 will not behave in a predictable manner. For example, if a ball lands directly on one of the rebound dampers 26, the ball may drop very rapidly and/or change in direction, relative to a ball which would strike the mesh at a position spaced from the rebound dampers 26.
As an alternative to the rebound dampers 26, dampers 35 (Figure 10A) may be used. The dampers 35 have a front surface 36 and a central aperture 37.
In Figures 10(a), (b), (c), (d) and (g), alternative rebound altering devices are shown. They have varying characteristics and may be positioned on the surface 15 to provide a pattern of return required. In Figure 10(d) the altering device is an increased weave density over a predetermined area.

Claims

1. A rebound device 10 for a ball game, said device 10 comprising a frame 11 to rest upon a support surface, a rebound surface 15 supported by the frame 11 and against which the ball may be hit to be returned to a user, said rebound surface 15 being defined by a generally planar sheet material 12 which is deformed by the ball impacting thereagainst, and rebound varying means 26 fixed to said rebound surface 15 and adapted to influence the projection and/or velocity of a rebounding ball having impacting against the rebound surface 15 at or adjacent said rebound varying means 26 as compared to a ball impacting against said rebound surface 15 at a position remote from said rebound varying means 26.

2. The rebound device 10 of Claim 1, wherein said rebound surface 15 is provided by a mesh 12, and said rebound varying means 26 is a plurality of rebound dampers 26 secured to said mesh 12.

3. The device 10 of Claim 2, wherein each rebound damper 26 has a head portion 27 against which a ball may impact, and a securing portion 28 located on the other side of said mesh 12, and a neck portion 29 extending through the mesh 12 and joining said head portion 27 and securing portion 28.

4. The rebound device 10 of Claim 3, wherein each rebound damper 26 has an annular groove 34 within which portions of the mesh 12 are located to retain the rebound dampers 26 in position.

5. The rebound device 10 of Claim 4, wherein the head portion 27 of each rebound damper 26 has ridges 30 against which a ball may impact.

6. A rebound damper 26 to be fixed to a flexible rebound sheet 12 of a rebound device 10, which sheet 12 has a front rebound surface 15 against which a ball impacts to be returned by the device, and a rear surface; said damper 26 having:
a head portion 27 to abut said rebound surface 15 so as to project away from said rebound surface 15;
a securing portion 28 to abut said rear surface;
a neck 29 joining said head portion 27 and securing portion 28, which neck portion 29 is adapted to pass through said rebound sheet 12; and
wherein said head portion 27 has outwardly facing surface irregularities 30 which engage the ball to vary the projection and/or velocity of the rebounding ball.

7 The rebound damper 26 of Claim 6 wherein said surface irregularities 30 are projecting ridges 30.

8. The rebound damper 26 of Claim 7 wherein said ridges 30 are elongated and extend radially from a central portion of said head portion 27.

9. The rebound damper 26 of Claim 8 wherein each ridge 30 has a triangular transverse cross section which diminishes in area from said central portion.