GB2548880A - Sports equipment - Google Patents

Abstract

A dartboard comprises a generally planar rear support member 14 and a plurality of fibres 16 which extend from the rear support member 14 in a direction that is substantially perpendicular to the plane of the rear support member 14. The fibres 16 are of substantially equal lengths and have free ends 17 which are substantially unconnected to each other. The free ends 17 of the fibres 16 form a front surface of the dartboard. The fibres 16 are synthetic fibres and/or are formed from a polymer.

Description

Title: Sports Equipment Description of Invention

This invention relates to sports equipment and in particular concerns targets at which projectiles will be thrown, such as dartboards.

Darts is a popular sport which is played widely throughout the world, in particular in North America, some European countries such as the UK and the Netherlands, and Japan.

Conventional dartboards are formed from fibres of sisal. The sisal is harvested and these fibres are combed extensively to straighten them. Once the combing process is complete a tube of parallel fibres is extruded, and slices of this tube are cut to form “biscuits”.

To form a dartboard, several biscuits (in some examples, around 60 biscuits) are placed onto a flat board or other surface. A metal band is placed around the biscuits and steadily contracted so that the fibres of the biscuits are compressed together. The biscuits are glued to the backboard (fig 3, 14) to prevent the sisal fibres from being pulled out of the board as the point of a dart is withdrawn from the board. The band is contracted to the size of the dartboard, and the free ends of the fibres which will form the front surface of the dartboard may then be levelled off and dyed to a desired colour. One or more metal pieces marking sub divisions on the board (known as the “spider”) is then stamped onto the front surface of the board using a special tool. The dartboard is then ready for use.

The main playing surface of the finished board comprises a large number of generally parallel fibres, which are compressed together, and have their free ends facing towards a player, i.e. generally in the direction from which incoming darts are likely to arrive. When a dart is thrown towards the board the narrow tip of the dart lodges between these parallel fibres, and the dart is held in place where it has struck the board.

Once the dart is removed, the fibres move together again to re-close the hole that has been formed by the tip of the dart, and the fact that the fibres are compressed together helps this to happen.

It is an object of the present invention to provide an improved dartboard construction.

Accordingly, one aspect of the present invention provides a dartboard comprising: a generally planar rear support member; and a plurality of fibres which extend from the rear support member in a direction that is substantially perpendicular to the plane of the rear support member, the fibres being of substantially equal lengths and having free ends which are substantially unconnected to each other, the free ends of the fibres forming a front surface of the dartboard, wherein the fibres are synthetic fibres and/or are formed from a polymer.

Advantageously, the fibres are entirely or substantially entirely formed from a single polymer.

Preferably, the cross-sectional structure and composition of each fibre is substantially the same along its length.

Conveniently, the diameter of each fibre is between around 0.07mm and 0.15mm.

Advantageously, the diameter of each fibre is around 0.075mm.

Preferably, the density of the fibres, when viewed in a direction perpendicular to the rear surface, is between around 51 million and 368 million fibres per m2.

Conveniently, all or part of the fibres are treated to improve the fire resistant properties thereof.

Advantageously, each fibre is formed from a synthetic polymer.

Preferably, each fibre is formed from a polyester.

Conveniently, each fibre is formed from polybutylene terephthalate (PBT).

Another aspect of the present invention provides method of forming a dartboard, comprising the steps of: providing a generally planar rear support member; arranging a plurality of polymer fibres and/or synthetic fibres on the rear support member, so that one end of each fibre lies on or near the rear support member and the fibre lies substantially perpendicular to the plane of the rear support member; and bonding one end of each fibre to the rear support member.

Advantageously, the step of arranging a plurality of fibres on the rear support member comprises arranging the fibres so that they are substantially unconnected to each other so that following the bonding step, the free ends of the fibres are substantially unconnected to each other.

In order that the invention may be more readily understood, embodiments thereof will now be described, by way of example, with reference to the accompany drawings, in which: figures 1 and 2 show a dartboard embodying the present invention; figure 3 shows a cross-sectional view of the dartboard of figures 1 and 2; and figures 4 to 6 show stages in the manufacture of a dartboard embodying the present invention.

Referring firstly to figures 1 and 2, a dartboard 1 embodying the present invention is shown. The outward appearance of the dartboard 1 is conventional, in that the dartboard generally takes the form of a short cylinder. The dartboard 1 has a flat or substantially flat front face 2 which is circular or approximately circular, and a parallel rear face 3, which is again circular or approximately circular and is of the same size and shape as the front face 2. A curved, outward facing sidewall 4 extends between the front face 2 and the rear face 3. A dividing frame 5 or spider is mounted on the front face 2 and (as is known in the art) serves to divide the front face 2 into a number of separate target areas or “beds”. The dividing frame 5 may be formed as one unitary item, either formed integrally or formed from a number of different elements which are welded or otherwise fixed together, or alternatively it may be provided in two or more parts which are independently attached to the front face 2 of the board 1.

As is known in the art, the dividing frame 5 includes first inner and outer circles 6,7, which lie generally on the centre of the front face 2 of the dartboard 1. The first inner and outer circles 6,7 defines “inner bull” and “outer bull” beds, respectively. The first inner circle 6 is spaced apart from the other parts of the dividing frame 5. Other than this, the parts of the dividing frame 5 are all attached to each other.

Several spokes 8 radiates outwardly from the first outer circle 7, and divide the front face 2 into a number of sectors. On a conventional dartboard there are 20 spokes 8, dividing the board into 20 sectors, each of which is associated with a scoring number, with the scoring numbers extending from 1 to 20.

Mounted partway along the spokes 8 are a second inner and outer circles 9,10, which are generally concentric with the first inner and outer circles 6,7, and spaced relatively close together. As the skilled reader will understand, on a conventional dartboard the area in any particular sector between the second inner and outer rings 9,10 is the “triple” bed for that sector, and a dart landing in this area registers a score of three times the regular score associated with that sector.

At or near the outer end of each spoke 8, third inner and outer circles 11,12 are fixed. Once again the third inner and outer circles 11,12 are each generally concentric with the first inner and outer circles 6,7, and are spaced relatively close together. The space between the third inner and outer circles 11,12 is the “double” bed for that sector, and a dart landing in this area registers a score which is double that of the regular score for that sector.

It will be understood that the dividing frame 5 serves to divide the front face 2 of the dartboard 1 into a number of regions into which darts may be thrown. The provision of wires or other thin bars between the areas serves to ensure that a dart must land clearly in one of the areas, so that that there can be no dispute as to the area in which a particular dart has landed.

In general, the wires or other bars that form the dividing frame 5 are made to be as thin as possible, in a direction facing directly outwardly from the front face 2 of the dartboard 1, to minimise the chance of a tip of an incoming dart directly striking one of these wires and rebounding from the board 1.

In addition to the dividing frame 5, a scoring ring may be affixed at or near the perimeter of the front face 2 of the dartboard 1. The scoring ring 19 comprises, in the example shown, a generally circular ring with a series of numbers 20 attached to the ring. These numbers 20 may, for example, be formed from lengths of wire which are twisted or otherwise formed into the shapes of the appropriate numerals.

The scoring ring 19 is arranged so that one number appears adjacent the outer end of each scoring sector with the number 20 corresponding to the score that is associated with each sector.

In the example shown the scoring ring 19 is in addition to, and separate from, the dividing frame 5. In other examples, a scoring indication may be formed integrally with the dividing frame 5. Preferably, the scoring ring 19 is separate from the dividing frame, so that scoring ring 19 may be rotated with respect to the dividing frame 5, thus allowing the wear on the various sectors of the dartboard to be spread evenly throughout the life of the dartboard.

Around the outer surface 4 of the dartboard a sturdy ring, such as a metal band, may be provided. The ring may, in a preferred embodiment, have a single break therein, with the free ends of the break being rigidly connected together, by welding or another convenient method.

The dartboard 1 may have, on its rear face 3, an attachment arrangement (not shown) for allowing the dartboard 1 to be affixed to a wall or other surface/feature at an appropriate height for play. For instance, the attachment arrangement may comprise a metal bracket with a downward-facing trough, which can be placed over the end of screw, nail or other protrusion which is fixed to a wall.

The front face 2 of the dartboard 1 may be coloured in any desired fashion. On a conventional board, sectors are alternatively dyed in black and white or beige colours, while the double and triple beds are dyed in alternating red and green colours. An outer region 13 of the front face 2, i.e. beyond the third outer ring 12, may be dyed a black colour.

This is, however, entirely a matter of preference and there are many different local variations on the traditional colour scheme.

The features of the dartboard described above are, thus far, conventional.

Figure 3 shows a schematic view of a part of a cross section through the dartboard 1 shown in figure 1, taken along a plane which bisects the board 1, passes through the inner bull bed, and is perpendicular to the front face 2 of the dartboard 1.

The view shown in figure 3 does not overlap or include any of the dividers which form part of the dividing frame 5.

As can be seen in figure 3, the dartboard 1 includes a support board 14, a rear surface of which forms the rear face 3 of the dartboard 1.

Protruding from the front surface 15 of the support board 14 are a large number of fibres 16. The fibres are generally parallel with one another, and face directly away from the support board 14. The fibres 16 are preferably closely bunched together and the spacing between fibres 16 is greatly exaggerated in figure 3 for purposes of clarity.

In accordance with the invention, the fibres 16 are formed from a polymer.

Preferably, each fibre is formed from the same polymer along its length, and is formed entirely or substantially entirely from that polymer.

As an alternative, each fibre may be coated, in that it comprises a central core with one or more surrounding layers. Preferably, both the core and the surrounding layer(s) are formed from polymers. In other embodiments, however, either the core or one or more of the surrounding layers may be formed from a polymer. Preferably, each fibre has a structure which is consistent along its length, i.e. the cross-sectional structure and composition of the fibre is the same or substantially the same no matter the point along the length of the fibre at which the fibre is cut.

The fibre used in the invention may comprise a man-made fibre derived from a natural source such as a cellulose fibre extracted from a natural source and processed. An example of this is fibres which are made from natural rubber. Preferably, however the fibre is a synthetic fibre, meaning a fibre which is wholly produced artificially, such as from petrochemicals. Examples are metal, glass and polymer fibres.

Synthetic polymer fibres are most preferred in the present invention. As is known in the art, polymer fibres are man-made fibres which may be produced from petrochemicals. Examples of polymers useful for the present invention include aliphatic or semi-aromatic polyamides such as nylon, and polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT) and polyethylene naphthalate (PEN). PBT is particularly preferred in the present invention, having mechanical properties particularly suitable for use in the article of the invention.

Other polymers useful in the fibres of the invention include phenol-formaldehyde (PF), polyvinyl chloride (PVC), polyolefins such as polypropylene (PP) and polyethylene (PE) and including long chain polyolefins such as ultra-high molecular weight polyethylene (UHMWPE), acrylic polyesters, pure polyester, aromatic polyamids (aramids), elastomers, polyurethane and elastolefin.

The fibres of the invention include homopolymers (wherein the monomers making up the polymer chain are identical) and copolymers (wherein the polymer chain is made up of at least two different monomers). For example polyethylene (PE) is a homopolymer wherein the monomers are ethylene and polypropylene (PP) is a homopolymer wherein the monomers are propylene. However the invention includes, as well as these homopolymers, copolymers such as a PE/PP copolymer. Copolymerisation may improve the mechanical characteristics of a homopolymer; for example PE/PP is more tough and flexible than homopolymeric PP. Other copolymers useful for the fibres if the invention include acrylonitrile butadiene styrene (ABS), styrene/butadiene copolymer (SBR), nitrile rubber, styrene-acrylonitrile, styrene-isoprene-styrene (SIS) and ethylene-vinyl acetate.

In preferred embodiments of the invention, the diameter of each fibre is between around 0.07mm and 0.15mm. More preferably, the diameter is around 0.07mm to 0.1 mm. Yet more preferably, the diameter of each fibre is around 0.075mm.

The fibres are preferably densely bunched together and each fibre will contact the fibres that immediately surround it. If the fibres are assumed to be packed together in a hexagonal lattice, with each fibre touching the surrounding fibres, then (assuming no compression of the fibres) the density of fibres is likely to be between around 51 million fibres/m2 (if the fibres have a diameter of 0.15mm) and 236 million fibres/m2 (if the fibres have a diameter of 0.07mm). In reality the density of fibres may be higher than this if the fibres are compressed together. It is anticipated that the radial (linear) compression of the fibres may be up to 20%, giving densities of around 80 million fibres/m2 to around 368 million fibres/m2.

The inventors believe that a finished board will contain around 4-6kg of polymer, most preferably about 5kg of polymer. The diameter of the circular area covered by the fibres is preferably around 45cm, and the fibres in the finished dartboard will each have a length of around 2.5cm.

It should be noted that the diameter of each individual fibre, as expressed above, should be taken to be the diameter of each individual fibre in isolation, i.e. not compressed by any surrounding fibres. When the fibres are compressed as part of a finished dartboard, the actual diameter of each fibre may be reduced or distorted through compression.

As can be seen in figure 3, each of the fibres 16 has a free end 17, which is the end furthest from the point at which the fibre 16 joins the support board 14. The fibres 16 are preferably not (aside from in the region where the fibres 16 meet the support board 14) joined or bonded to each other. This means that, when a dart is thrown towards to the dartboard 1, the tip of the dart may pass between the free ends 17 of some of the fibres 16, and lodge between the fibres 16 to be held in place until it is manually removed by the player or another person.

Preferably, the length of each fibre 16 from the point at which it meets the support board 14 to its free end 17 is the same, so that the front surface 2 of the board is substantially flat, level, and parallel with the support board 14. A method of manufacturing the dartboard 1 will now be described.

As a first stage, a large number of fibres 16 are placed with a generally circular band 18, which may be formed from metal, plastic or any other suitable material. The fibres 16 are all generally parallel with each other, and also parallel with the main axis of the band 18. The band 18 is preferably of approximately the same height as the fibres 16, which (as discussed above) may be around 2.5cm. At this stage, the fibres 16 may be relatively loosely bunched together. Each fibre is preferably separate from the others, and is not joined or bonded to any of the other fibres 16 at this stage. The fibres 16 and band 18 may be rested on a temporary support surface 20 to help maintain the alignment of the fibres 16.

As a next stage, the band 18 is contracted to reduce the diameter thereof, preferably while remaining circular or substantially circular in shape. As this occurs, the fibres 16 within the band will become more closely bunched and compressed together. In a preferred process, the band is contracted by a compressor (a known machine in the art), and free ends of the band 18 will overlap as the compression takes place. Once the band 18 has been sufficiently contracted, the free ends of the band 18 are spot-welded to maintain the band 18 in its contracted state. Figure 5 shows the situation once this contraction has taken place. A generally circular support board 14 is provided, and the support board may be formed from a robust material such as MDF, wood or metal. In a preferred method a face of the support board 14 is coated with a suitable glue, and the fibres 16 are then placed onto the support board 14 while the glue is still wet. The glue is allowed to dry, and the result is shown in figure 6.

In alternative methods, the fibres 16 may be placed against a support board, and the support board may be heated so that the ends of the fibres 16 that lie closest to the support board 14 melt at least partially, thus bonding the fibres 16 to the support board 14.

The density of fibres will now be as discussed above.

The density of fibres as chosen so that, when a dart having a tip of a standard diameter is thrown towards the board, the tip will lodge easily between the fibres, and be held in place until it is removed, at which point the fibres will move together to re-close the gap caused by the tip of the dart.

If the density of fibres is too high it may be difficult for a dart, particularly a softly-thrown or unusually wide dart, to lodge between the fibres 16. The dart may penetrate to an insufficient depth, and the weight of the remainder of the dart will then pull the dart out of the board. If the fibres are too densely packed, they may also fail to part effectively to allow the tip of the dart to lodge between them, and use of board may damage the fibres 16 at an unacceptably high rate.

If the fibres are too loosely packed together, they may not grip a dart effectively, so that it falls out of the board and it is not held in place until it is manually removed.

As a final step, the free ends 17 of the fibres 16 may be levelled off, for instance by a sanding-type operation, to give a smooth finish. These free ends 17 will ultimately form the front surface 2 of the finished dartboard, which shoul be generally flat. A dividing frame 5, as discussed above, may then be stamped onto the front surface of the fibres 16, or may alternatively be placed on the free ends 17 of the fibres 16 and bonded in place, for instance by gluing or heating/welding or any other suitable method.

All or part of the fibres 16 may be dyed to be an appropriate colour. This dying step may take place at any point in the manufacturing process, and may be before or after the dividing frame 5 is attached. Different regions of the fibres 16 may, as discussed above, be dyed different colours.

In some embodiments, fibres having a certain “base colour” may be used, and some regions of the fibres 16 may not be dyed, so that base colour of fibres forms the colour of that part of the finished dartboard.

All or part of the fibres 16 may also be treated to improve the fire-resistant properties thereof.

Once these steps have been completed, the dartboard 1 is effectively finished and ready for use. A mounting arrangement, as discussed above, may be attached to the rear surface 4 of the dartboard 1.

It is expected that a dartboard constructed as described above will have significant advantages over conventional dartboard constructions. Because conventional dartboards are formed from organic material, the supply of the necessary materials can be subject to fluctuations in availability and price because of poor harvests and other factors which are difficult or impossible to control. Moreover, because of the nature of conventional dartboards, in humid conditions such as warm climates or certain indoors environments such as pubs, the board may swell and “bloom” as the organic material of the sisal fibres absorbs water. It will be understood that the proposed constructions described above will be less subject to these difficulties. In addition, it is expected that synthetic polymers will suffer substantially less ‘wear’ than organic fibres during use, and therefore dartboards formed in accordance with the invention will degrade less and last longer.

While the above discussion focuses on dartboards, other targets may also be formed in accordance with the invention, such as archery targets and targets for children’s games.

When used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps or integers are included. The terms are not to be interpreted to exclude the presence of other features, steps or components.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims (15)

Claims

1. A dartboard comprising: a generally planar rear support member; and a plurality of fibres which extend from the rear support member in a direction that is substantially perpendicular to the plane of the rear support member, the fibres being of substantially equal lengths and having free ends which are substantially unconnected to each other, the free ends of the fibres forming a front surface of the dartboard, wherein the fibres are synthetic fibres and/or are formed from a polymer.

2. A dartboard according to claim 1, wherein the fibres are entirely or substantially entirely formed from a single polymer.

3. A dartboard according to claim 1 or 2, wherein the cross-sectional structure and composition of each fibre is substantially the same along its length.

4. A dartboard according to any proceeding claim, wherein the diameter of each fibre is between around 0.07mm and 0.15mm.

5. A dartboard according to claim 4 wherein the diameter of each fibre is around 0.075mm.

6. A dartboard according to any proceeding claim, wherein the density of the fibres, when viewed in a direction perpendicular to the rear surface, is between around 51 million and 368 million fibres per m2.

7. A dartboard according to any proceeding claim wherein all or part of the fibres are treated to improve the fire resistant properties thereof.

8. A dartboard according to any preceding claim, wherein each fibre is formed from a synthetic polymer.

9. A dartboard according to claim 8, wherein each fibre is formed from a polyester.

10. A dartboard according to claim 9, wherein each fibre is formed from polybutylene terephthalate (PBT).

11. A method of forming a dartboard, comprising the steps of: providing a generally planar rear support member; arranging a plurality of polymer fibres and/or synthetic fibres on the rear support member, so that one end of each fibre lies on or near the rear support member and the fibre lies substantially perpendicular to the plane of the rear support member; and bonding one end of each fibre to the rear support member.

12. A method according to claim 11, wherein the step of arranging a plurality of fibres on the rear support member comprises arranging the fibres so that they are substantially unconnected to each other so that following the bonding step, the free ends of the fibres are substantially unconnected to each other.

13. A dartboard substantially as hereinbefore described, with reference to the accompanying drawings.

14. A method substantially as hereinbefore described, with reference to the accompanying drawings.

15. Any novel feature or combination of features disclosed herein.