AU573559B2

AU573559B2 - Rebound screen for ball games

Info

Publication number: AU573559B2
Application number: AU23429/84A
Authority: AU
Inventors: Charles William Dransfield
Original assignee: Dransfield C W
Current assignee: Dransfield C W
Priority date: 1982-12-24
Filing date: 1983-12-22
Publication date: 1988-06-16
Anticipated expiration: 2003-12-22
Also published as: AU2342984A

Description

REBOtMD SCREEN FOR BALL GAMES TECHNICAL FIELD

This invention relates to apparatus for the playing of a game in which players strike a ball at a substantially vertical surface so that the ball rebounds therefrom to return to the playing area. Such a game, which is played in a manner analogous to the game of tennis, is known.

BACKGROUND ART

In the known game referred to, the court comprises a rectangular area with a vertical, resilient rebound screen or net at the end remote from the base line, and a dead ball area extending across the court adjacent to the net. The playing area of the court is divided longitudinally by a centre line to provide service areas.

The rebound screen^' employed in the known game comprises a peripheral frame in which a net is supported by springs spaced at intervals around the four sides of the net. The net extends over the full height of the frame and is provided with means such as a horizontal line or a change of colour of the net material, defining a net service line above which a service must strike the net to be fair.

In the play of this prior art game, and particularly where it is adapted for use in restricted areas such as carports or indoor areas, it has been found that the ability of the ball to rebound elastically from the lower portion of the net causes difficulty in play, and restricts the usefulness of this game in restricted areas. Experiment has shown that a game of this type is in fact improved, in unrestricted as well as restricted areas, if a fair return cannot be made to the lower region of the net. A further disadvantage of the prior art game in its application to reduced playing areas, is the inability to scale the elastic properties of the net₇with the result that strongly hit returns or services too easily go out beyond the base line.

DISCLOSURE OF THE INVENTION

These disadvantages of the prior art are sought to be overcome by the present invention, which in one broad form resides in a rebound screen comprising an upright structure supporting resilient means from which a striking ball will rebound, service line means delineating on said resilient means a service region which excludes a service fault region of said resilient means immediately below said service region, characterised in that said apparatus further comprises means defining a modified rebound region between said service fault region and the base of said screen.

Preferably, the means defining the modified rebound region provides a substantially inelastic rebound, and may consist of a sheet of inelastic, flexible material, or a sheet of rigid material.

In order to enable adjustment of the degree of rebound from the net, in the preferred form of the invention the net is supported from a frame by supporting and tensioning members and means are provided for adjusting the net tension.

OMH BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

Fig 1 is a front elevation of a rebound tennis screen embodying the present invention; Fig 2 is a side elevation of the screen of Fig 1;

Fig 3 is a fragmentary detail showing the manner of support of the net in the frame; and

Fig 4 is a plan of a suitable court layout.

MODES FOR CARRYING OUT THE INVENTION

The net illustrated by way of example in the accompanying drawings comprises a frame 10, which may be of steel or aluminium tube. The frame is provided with a cross- member 11 and is supported by means of legs 12 and struts 13. A net 14 is mounted within the frame 10 above the cross- member 11, by means of adjustable straps 15 which are passed around the frame 10 and around a continuous cord 16 suitably of nylon, which is threaded through the net around its periphery. The cord 16 is supported close to the corners of the frame by passing through eyes at the end of bolts 15a.

The area below the cross-member 11 and the base of the frame 10 is filled by a sheet 17 of flexible, inelastic material such as a strong plastics material, and this is supported from the frame and the cross-member 11 by means of straps 18 which pass through eyelets provided in the sheet for that purpose.

As shown in Fig 3, the adjustable straps 15 which may be nylon or other suitable plastics material, are provided with a head 19 through which the tail 20 is passed and friσtionally gripped. The length of the cord 16 is such that it is always in tension when supported in the frame 10, and it will be understood that this tension, and thereby the tension in the net 14, may be increased by shortening the straps 15, or decreased by loosening these straps. Decreasing the net tension reduces the velocity with which a ball will rebound from the net, and adjusts the net to a smaller playing area. Conveniently, the net tension is adjusted so that a ball hit to the net with maximum strength will rebound to the base line. The tension in the net is mainained evenly throughout its width and height by virtue of the fact that it may move freely at its periphery relative to the cord 16, while the cord 16 is freely supported by the straps 15 and the eyes of the bolts 15a.

As the sheet 17 will exhibit no elastic rebound properties, balls which strike this area of the net structure will fall dead and the players will know that the stroke has been lost.

Due to the presence of the region defined by the sheet 17, there is no need for a dead ball area^* to be defined on the court as in the prior art, and this is found to improve the play of the game, as well as the ability of the players and referee to distinguish fair returns.

At a level approximately one quarter of the total height of the net 14 above the cross-member 11 a net service line 21 is provided. Although this is shown as a line for ease of illustration, it may comprise the boundary between areas of the net 14 of different colour or different colour saturation.

To assist the reader in understanding the significance of the design of a net according to the present invention, the manner in which the game, known as Rebound Tennis, is played will now be described. As shown in Fig 4, the boundaries of the court are defined by a base line 22, net line 23 and side lines 24. The preferred size of the court is approximately 3.7 metres wide and 5 metres long, and a ground service line 25 is provided across the court approximately 1.4 metres from the net line 23. These are sizes suitable for championship play, but the reader will appreciate that the court may be scaled down dramatically, and a satisfactory game can be played on a court which is 3 metres by 4 metres, or even smaller. The game may also be played on a larger court.

Racquets employed in the game should be smaller and have reduced string tension compared with conventional tennis racquets, and the ball should have reduced pressure.

The ball is served from the side of the centre line with one foot behind the base line, and a fair service must strike the net 14 above the net service line 21 and rebound into the court past the ground service line 25. A player serves from alternate sides after each point is won until he loses the stroke. A service which strikes the net below the net service line 21, or strikes the net 14 above the service line but fails to land fairly is a fault, while a service ball which strikes the panel 17, or any part of the frame 10, loses the stroke. A fair return is a return in which the ball is returned off the first bounce or volley to strike the net 14 and return to fall within the boundaries of the court or to be struck by the opponent.

When a ball strikes the net at any part of its surface ^• other than the edge regions, it will of course rebound from the net with an angle of reflection substantially equal to the angle of incidence. As a consequence of the manner in which the net is supported according to the invention, however, and particularly when as is preferred the cord 16 is substantially inelastic, if the ball strikes the net near one of its edges the direction of rebound will be altered dramatically and this effect will increase as the point of impact approaches the cord 16, where the ball will tend to return along the path of its approach. This enables players, with practise, to develop skills not possible in the prior art game where the manner of support of the net does not provide these rebound characteristics.

The embodiment of the invention described above is, of course, only one example of the application of the present invention. It will be apparent that other means may be adopted whereby a modified rebound area is provided. For example, instead of the sheet 17, a metal panel may be employed. Alternatively, the net 14 may be continued to the base of the frame 10 and the lower portion of the net treated, for example by attaching a sheet of non-resilient material such as cloth or plastics, to provide a modified rebound characteristic.

Similarly, it will be appreciated that means other than those described may be employed for adjusting the net tension.

CMPI

"WIFO

Claims

1. A rebound screen for a ball game comprising an upright structure supporting resilient means from which a striking ball will rebound, service line means delineating on said resilient means a service region which excludes a service fault region of said resilient means immediately below said service region, characterised in that said apparatus further comprises means defining a modified rebound region between said service fault region and the base of said structure.

2. A screen according the claim 1 wherein said resilient means provides an elastic rebound of a striking ball and said means defining a modified rebound region provides a substantially inelastic rebound for said ball.

3. A screen according to claim 2 wherein said means defining a modified rebound region comprises a sheet of substantially inelastic, flexible material mounted on said structure and extending across said modified rebound region.

4. A screen according to claim 2 wherein said means defining a modified rebound region comprises a sheet of rigid material mounted on said structure and extending across said modified rebound region.

5. A screen according to claim 1 wherein said resilient means comprises a net and said upright structure comprises a frame extending around the periphery of said net, the periphery of said net being attached to a cord extending continuously around said net, said attachment permitting relative movement between said net and said cord in the longitudinal direction of said cord and support means by which said cord is supported from said frame.

6. A screen according to claim 5 wherein said support means allows relative movement between said cord and said frame in the longitudinal direction of said cord.

7. A screen according to claim 6 wherein said cord is substantially inelastic.

8. A screen according to claim 5 or claim 7 wherein said support means is adjustable to vary the spacing of said cord from said frame.

9. The screen according to claim 8 wherein said support means comprises a pluraliy of straps embracing said cord and said frame at spaced intervals around the periphery of said net.