AU2020102495A4

AU2020102495A4 - Ball

Info

Publication number: AU2020102495A4
Application number: AU2020102495A
Authority: AU
Inventors: Aaron Lilly
Original assignee: Swinga Cricket Pty Ltd
Current assignee: Swinga Cricket Pty Ltd
Priority date: 2020-09-29
Filing date: 2020-09-29
Publication date: 2020-11-19
Anticipated expiration: 2028-09-29

Abstract

Disclosed is a ball for use in sport or recreation and that is to be delivered through air. The ball may comprise a body having a smooth portion side and a textured portion side having a surface roughness that is greater than the smooth portion. The ball may also have a band extending around the body and being integral with the body. The band may be proud of the body and separates the smooth and textured portions. When the ball is delivered through the air, the ball may deviate from an expected trajectory towards either the smooth portion side or the textured portion side of the ball. 18 22b 22c 16 10 )o 20 14 0 00 000 O 0 022e2f Figure 1 22d A 18 14 0 0 Figure 2

Description

18 22b 22c 16

)o 20

14 0

00 000

O 0

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Figure 1 22d

A

18

14 0 0

Figure 2

Ball

Field The disclosure relates to balls used for sports or recreation, such as a training ball used for batting practice.

Background In many ball sports a skilled player is able to swing a ball during its flight through the air. For example, in cricket, a skilled fast bowler is able to deliver a swinging ball depending on how the ball is bowled and the different surface textures of the ball. The purpose of making the ball swing is to make it harder for the batsman to hit the ball.

To prepare batsman for playing against a swinging ball, batsman will practice hitting swinging deliveries such as in cricket nets with a bowling machine. Unfortunately, existing training balls, such as those used with bowling machines, are unable to be swung and/or are larger than a normal "match" cricket ball which provides inadequate training. An example of a normal match cricket ball is a Kookaburra Turf ball made by cricket ball manufacturer Kookaburra. The reason why a training ball is used is that match cricket balls are comparably more expensive than training balls. In addition, a match cricket ball may only be able to produce swinging deliveries for up to 30-40 deliveries, which is significantly less than what a batsman will hit during a training session.

It is to be understood that, if any prior publication is referred to herein, such reference does not constitute an admission that the publication forms part of the common general knowledge in the art, in Australia, or any other country.

Summary Disclosed is a ball for use in sport or recreation and that is to be delivered through air, the ball comprising a body having a smooth portion side and a textured portion side having a surface roughness that is greater than the smooth portion side; a band extending around the body and that is integral with the body, the band being proud of the body and separating the smooth portion side and textured portion side; wherein, when the ball is delivered through the air, the ball deviates from an expected trajectory to an actual trajectory that is in a direction towards either the smooth portion side or the textured portion side.

The smooth portion side may define a first hemisphere and the textured portion side may define a second hemisphere. A meeting point of the hemispheres defines an equator of the ball. The band may run around the equator. The textured portion may be a dimpled surface. A diameter of the dimples may decrease in a direction towards a centre of the dimpled surface. Put another way, a diameter of the dimples may decrease in a direction extending away from the band.

Disclosed is a ball for use in sport or recreation and that is to be delivered through air, comprising: a body having a smooth side and a dimpled side having a plurality of dimples, the smooth and dimpled side being integral, wherein a diameter of the dimples decreases in a direction extending towards a centre of the dimpled side, and wherein, when the ball is delivered through the air, the ball deviates from an expected trajectory to an actual trajectory that is in a direction towards either the smooth portion side or the textured portion side.

The ball may be formed from polyurethane. A density of the ball may range from about 0.69 g/cm 3 to about 0.74 g/cm 3. A diameter of the ball may range from about 71 mm to about 73 mm. The ball may have a weight of about 140 g to about 160 g, similar to that of a normal match cricket ball.

The deviation from the expected trajectory may be determined by a travel speed of the ball. When the ball travels at or below a threshold speed the ball may deviate towards the textured portion side of the ball. When the ball travels above the threshold speed the ball may have a propensity to deviate towards the smooth portion side of the ball. The term ""propensity" as used herein is to mean that when the ball travels above the threshold speed the ball can deviate towards the smooth portion side but may still deviate towards the textured portion side (or dimpled side) depending on a throwing or bowling action used to propel the ball through the air. The threshold speed may be about 80 km/h to about 130 km/h. The threshold speed may be about 80 km/h, 90 km/h, 95 km/h, 100 km/h, 105 km/h. 110 km/h, 120 km/h or 130 km/h.

The disclosure also provides a method of making a ball for use in sport or recreation and that is to be delivered through air, the ball having a body having a smooth portion side and a textured portion side having a surface roughness that is greater than the smooth portion side, and a band extending around the body and being integral with the body, the band being proud of the body and separating the smooth portion side and textured portion side, the method comprising: providing a first mould section having a concave surface that forms the smooth portion and a second mould section having a textured concave surface that forms the textured portion; joining the first and second mould sections together to form a mould, wherein forming the mould provides a circumferential channel that forms the band; injecting a precursor material into the mould; and curing the precursor material to form the ball. The precursor material may be an uncured polyurethane, such as a diol and diisocyanate.

Brief Description of Figures Embodiments will now be described by way of example only with reference to the following non-limiting Figures: Figure 1 shows a perspective view of an embodiment of a ball; Figure 2 shows a top view of the embodiment shown in Figure 1; Figure 3 shows a partial cross-section of region A in Figure 2; Figure 4 shows a side view of the embodiment shown in Figure 1; and Figure 5 is a schematic representation of swinging action of an embodiment of a ball.

Detailed Description Disclosed is a ball for use in sport or recreation and that is to be delivered through air. In the embodiments shown in the Figures, the ball 10 is a cricket training ball. By cricket training ball, it is meant a ball that is used for cricket training purposes, such as in the use of bowling machines or throwing device. The ball 10 has a body having two sides. A first side has a smooth portion which is the form of first smooth side 14. A second side has a textured portion which is in the form of dimpled side 16. The dimpled side 16 has a plurality of dimples 20. The dimples 20 occupy at least a portion of the dimpled side 16. The dimpled side 16 has an overall surface roughness that is greater than the smooth side 14. It should be appreciated that at local or micro-scales, a point surface roughness (e.g. a area of -1mm 2 ) of the smooth side may be the same as the dimple side 18. In this way, the surface roughness refers to the roughness at a macro scale.

The smooth side 14 occupies approximately half a surface area of the ball 10 and the dimpled side 16 occupies approximately the other half of the surface area of the ball 10. In this way, the smooth side 14 can be considered a smooth hemisphere and the dimpled side 16 can be considered a dimpled hemisphere. The meeting point of the two hemispheres defines an equatorial plane (i.e. an equator). The equatorial plane is depicted as dashed line E in Figure 3.

A band in the form of a seam 18 extends around the ball 10. The seam 18 runs around the equator of the ball 10. Put another way, the seam 18 is located on a major circumference of the ball 10. The seam 18 extends outwards so as to sit proud of the surface of the ball 10. In the embodiment shown in the Figures the seam 18 separates or delineates the smooth side

14 and the dimpled side 16. The seam 18 helps to replicate a stitched seam of a normal match cricket ball.

The band 18 and sides 14 and 16 are integral. Accordingly, the ball 10 is formed as a one piece construction. In an embodiment, the ball is made using a two-part mould, such as an aluminium mould, where one part defines side 14 and the other part defines side 16. The seam 18 can be defined by a channel that is formed when the two parts of the mould come together. Having the band 18 and sides 14 and 16 be integral helps to improve a longevity of the ball. For example, training balls that are formed from two pieces and that are joined together, such as with glue and/or stitching, typically break at the join.

Now making reference to Figure 5, in the absence of the dimpled side 16 the ball 10 would travel straight along an expected trajectory ET. However, the dimpled side 16 results in the ball 10 deviating or swinging away from an expected trajectory (ET) towards an actual trajectory (AT) that is offset from the expected trajectory in a direction towards the dimpled side 16. The actual trajectory AT has the same or similar flight characteristics as a normal match cricket ball. Accordingly, in an embodiment, the ball 10 has similar flight characteristics as a normal match cricket ball. The deviation from the ET to the AT is caused by relative differences in boundary layer airflow over the smooth side 14 and dimpled side 16. It should be noted that the deviation from the expected trajectory ET can be towards the smooth side 14 (not shown in Figure 5). This is known as reverse swing and is determined in part by a ball age and/or travel speed of the ball through the air.

The seam 18 has a generally rectangular cross-section in a plane extending perpendicular to the equatorial plane E. A corner defined by an intersection of a sidewall and top of the seam 18 can be rounded. In an embodiment, the band 18 has a rounded cross-section instead of a rectangular cross-section. As best seen in Figure 3, the band 18 has a width W that is greater than a height H. In an embodiment a ratio of W:H is about 12:1. In an embodiment, W is 2-10 mm and H is 0.1 - 3 mm. In an embodiment, W is 6.0 mm and H is 0.5 mm. Generally, a seam 18 with a height H greater than 0.5 mm and a width W greater than 6.0 mm does not have similar flight characteristics to a normal match cricket ball. However, for training purposes, it may be desirable to have a ball that deviates more or less than a regular match cricket ball. It is important to note that Figure 3 is not drawn to scale and is only a schematic representation.

The dimpled surface 16 has a plurality of dimples 20. In the embodiment shown in the Figures, the dimples 20 are arranged into six groups 22a, 22b, 22c, 22d, 22e and 22f. Each group 22a-22f is arranged around a progressively smaller respective minor circumference. As best shown in Figure 3, the circumference of each group is aligned on a plane (e.g. E' E.') that is parallel to the equatorial plane E. For example, the dimples 20 in group 22a are arranged on a minor circumference that is aligned on plane E', the dimples 20 in group 22b are arranged on a minor circumference that is smaller than the minor circumference of group 22a and that is aligned on plane E", and so on for each group. The area within a perimeter defined by the sixth group 22f forms a side face 24. The side face 24 is centered on the pole 16a of the dimpled surface 16. The pole 16a is represented by a dashed dot in Figure 4 for illustrative purposes only to help describe embodiments of the ball 10. In the embodiment shown in the Figures the side face 24 acts as a location where insignia or a logo can be positioned. If textured insignia or a logo was positioned on the smooth side 14 it would increase a surface roughness of the smooth side 14 which could affect the flight of the ball through the air. Note that for clarity the first group 22a has been omitted from Figure 4. The smooth side 14 could have non-textured printed insignia or logos.

The dimples 20 in each group are equidistantly spaced around each respective minor circumference. The number of dimples 20 in each group depends on the minor circumference and the diameter of the dimples 20. In an embodiment, the groups 22a-22f have the number of dimples 20 outlined in table 1.

Table 1 Group Number of dimples 20 22a 28 22b 29 22c 26 22d 23 22e 17 22f 12

The dimples 20 have a diameter ranging from about 4.0 mm to about 8.0 mm. In an embodiment the dimples 20 have a diameter ranging from about 5.6 mm to about 6.3 mm. The dimples have a depth ranging from about 0.5 mm to about 2.5 mm. In an embodiment the dimples 20 have a depth ranging from about 1.3 mm to about 1.7 mm. A diameter and depth of the dimples may taper down from the first group 22a to the sixth group 22f (i.e. in a direction extending away from the seam 18 or a direction extending towards a centre e.g. side face 24 of the dimpled side 16). For example, in an embodiment, the dimples 20 in the first group 22a have a diameter of about 6.3 mm and a depth of about 1.7 mm, the dimples of the fourth group 22d have a diameter of about 5.9 mm and a depth of about 1.5 mm, and the dimples 20 of the sixth group 22f have a diameter of about 5.6 mm and a depth of about 1.3 mm.

The ball 10 is formed from a plastic. The ball may be formed from a polyurethane. A density of the ball may range from about 0.69 g/cm 3 to about 0.74 g/cm 3 . A weight of the ball 10 may range from about 140 g to about 160 g. In an embodiment a weight of the ball 10 ranges from about 145 g to about 155 g. A diameter of the ball 10 along an axis extending from the smooth side 14 to the dimpled side 16 ranges from about 71 mm to about 73 mm. In an embodiment the weight and diameter of the ball is the same, or substantially similar, to a weight and diameter of a normal match cricket ball.

In an embodiment, the ball 10 has the same, or substantially similar, bounce characteristics as a normal match cricket ball. Having the same or similar bounce characteristics as a normal match cricket ball means that the ball 10 can in an embodiment provide a batsman with game-like conditions during training. Existing training cricket balls are unable to provide game-like conditions because they are either not dimensioned or weight the same as a cricket ball, have difference bounce characteristics and/or had different flight characteristics. In an embodiment, the ball 10 has a bounce ratio of about 30% to about 40%, such as about % to about 40%. The "bounce ratio" means a percentage height that the ball will bounce relative an initial drop height. For example, in an embodiment, the ball 10 bounces to a height of 40 cm when dropped form an initial height of 100 cm. In another example, the ball bounces to a height of 70 cm when dropped from an initial height of 200 cm.

Existing training cricket balls either do not swing with game-like conditions, are larger than a normal match cricket ball, and/or have different bounce characteristics. By having a diameter (i.e. size) and weight of the ball 10 be the same or substantially similar to a diameter and weight of a normal match cricket ball, the ball 10 is able to more accurately mimic a normal match cricket ball (i.e. in terms of size and bounce) during training and practice. The dimples also allow the ball 10 to swing in flight, which when combined with the size and weight, means that batsmen can practice batting against game-like swing bowling using a training ball. After a number of deliveries (e.g. greater than 100) the ball 10 begins to age and instead of swinging to a dimpled side 16 the ball may start to swing in a direction towards the smooth side 14. This "reverse" in swing direction is similar to an aged normal match cricket ball.

In an embodiment, the direction of deviation from the expected trajectory is determined by a speed of the ball 10 through the air. When the ball travels at or below a threshold speed the ball 10 deviates towards the dimpled side 16 of the ball 10. This is considered normal swing. However, when the ball 10 travels at a speed greater than the threshold speed the ball 10 has the ability to deviates towards the smooth side 14. This is considered reverse swing. It should be noted that the ability to reverse swing the ball 10 is also dependent upon the delivery or throwing technique used to propel the ball 10 through the air. Therefore, the ball can deviate to either the smooth side 14 or the dimpled side 16. The threshold speed may be about 80 km/h to about 130 km/h, such as 95 km/h to 115 km/h. The threshold speed may be about 80 km/h, 90 km/h, 95 km/h, 100 km/h, 105 km/h. 110 km/h, 120 km/h or 130 km/h.

The textured portion is shown in the Figures as being a dimpled surface, but the textured portion is not limited to the use of dimples. Other types of textures can be used to allow the ball to swing during delivery through the air.

The embodiments shown and described with reference to the Figures relate to a training cricket ball. However, the disclosure is not limited to a training cricket ball. For example, a training baseball having the smooth side 14 and dimpled side 16 could be used. A baseball does not have a seam like a cricket ball. Accordingly, the seam 18 is not required in all embodiments.

In the claims which follow and in the preceding description of the disclosure, except where context requires otherwise due to expressed language or necessary implications, the word "comprise" or variants such as "comprises" or "comprising" is used in an inclusive sense i.e. to specify the presence of the state features but not to preclude the presence or addition of further features in various embodiments.

Claims

1. A ball for use in sport or recreation and that is to be delivered through air, comprising: a body having a smooth portion side and a textured portion side having a surface roughness that is greater than the smooth portion side; and a band extending around the body and being integral with the body, the band being proud of the body and separating the smooth portion side and the textured portion side; wherein, when the ball is delivered through the air, the ball deviates from an expected trajectory to an actual trajectory that is in a direction towards either the smooth portion side or the textured portion side.

2. A ball according to claim 1, wherein the textured portion is a dimpled surface.

3. A ball according to claim 2, wherein a diameter of the dimples decreases in a direction extending towards a centre of the dimpled surface.

4. A ball for use in sport or recreation and that is to be delivered through air, comprising: a body having a smooth side and a dimpled side having a plurality of dimples, the smooth and dimpled side being integral; and wherein a diameter of the dimples decreases in a direction extending towards a centre of the dimpled side; wherein, when the ball is delivered through the air, the ball deviates from an expected trajectory to an actual trajectory that is in a direction towards either the smooth portion side or the textured portion side.

5. A ball according to any one of the previous claims, wherein when the ball travels below a threshold speed the ball deviates towards the textured portion side and when the ball travels above the threshold speed the ball has a propensity to deviate towards the smooth portion side.